Build static libaom without internal deps in CMake.

Change the internal lib targets so that external apps
need link only libaom instead of all internal library
targets and libaom.

BUG=aomedia:76,aomedia:609

Change-Id: I38862fcd90cb585300b6b23e8558f78a1934750f
diff --git a/aom_dsp/aom_dsp.cmake b/aom_dsp/aom_dsp.cmake
index f39da7c..9182d35 100644
--- a/aom_dsp/aom_dsp.cmake
+++ b/aom_dsp/aom_dsp.cmake
@@ -415,7 +415,9 @@
 function (setup_aom_dsp_targets)
   add_library(aom_dsp_common OBJECT ${AOM_DSP_COMMON_SOURCES})
   list(APPEND AOM_LIB_TARGETS aom_dsp_common)
-  add_library(aom_dsp STATIC $<TARGET_OBJECTS:aom_dsp_common>)
+  create_dummy_source_file("aom_av1" "c" "dummy_source_file")
+  add_library(aom_dsp OBJECT "${dummy_source_file}")
+  target_sources(aom PRIVATE $<TARGET_OBJECTS:aom_dsp_common>)
   list(APPEND AOM_LIB_TARGETS aom_dsp)
 
   # Not all generators support libraries consisting only of object files. Add a
@@ -425,112 +427,107 @@
   if (CONFIG_AV1_DECODER)
     add_library(aom_dsp_decoder OBJECT ${AOM_DSP_DECODER_SOURCES})
     set(AOM_LIB_TARGETS ${AOM_LIB_TARGETS} aom_dsp_decoder)
-    target_sources(aom_dsp PRIVATE $<TARGET_OBJECTS:aom_dsp_decoder>)
+    target_sources(aom PRIVATE $<TARGET_OBJECTS:aom_dsp_decoder>)
   endif ()
 
   if (CONFIG_AV1_ENCODER)
     add_library(aom_dsp_encoder OBJECT ${AOM_DSP_ENCODER_SOURCES})
     set(AOM_LIB_TARGETS ${AOM_LIB_TARGETS} aom_dsp_encoder)
-    target_sources(aom_dsp PRIVATE $<TARGET_OBJECTS:aom_dsp_encoder>)
+    target_sources(aom PRIVATE $<TARGET_OBJECTS:aom_dsp_encoder>)
   endif ()
 
   if (HAVE_SSE2)
-    add_asm_library("aom_dsp_common_sse2" "AOM_DSP_COMMON_ASM_SSE2" "aom_dsp")
+    add_asm_library("aom_dsp_common_sse2" "AOM_DSP_COMMON_ASM_SSE2" "aom")
     add_intrinsics_object_library("-msse2" "sse2" "aom_dsp_common"
-                                   "AOM_DSP_COMMON_INTRIN_SSE2" "aom_dsp")
+                                   "AOM_DSP_COMMON_INTRIN_SSE2" "aom")
 
     if (CONFIG_AV1_ENCODER)
       add_asm_library("aom_dsp_encoder_sse2" "AOM_DSP_ENCODER_ASM_SSE2"
-                      "aom_dsp")
+                      "aom")
       add_intrinsics_object_library("-msse2" "sse2" "aom_dsp_encoder"
-                                    "AOM_DSP_ENCODER_INTRIN_SSE2" "aom_dsp")
+                                    "AOM_DSP_ENCODER_INTRIN_SSE2" "aom")
     endif()
   endif ()
 
   if (HAVE_SSE3 AND CONFIG_AV1_ENCODER)
-    add_asm_library("aom_dsp_encoder_sse3" "AOM_DSP_ENCODER_INTRIN_SSE3"
-                    "aom_dsp")
+    add_asm_library("aom_dsp_encoder_sse3" "AOM_DSP_ENCODER_INTRIN_SSE3" "aom")
   endif ()
 
   if (HAVE_SSSE3)
-    add_asm_library("aom_dsp_common_ssse3" "AOM_DSP_COMMON_ASM_SSSE3" "aom_dsp")
+    add_asm_library("aom_dsp_common_ssse3" "AOM_DSP_COMMON_ASM_SSSE3" "aom")
     add_intrinsics_object_library("-mssse3" "ssse3" "aom_dsp_common"
-                                  "AOM_DSP_COMMON_INTRIN_SSSE3" "aom_dsp")
+                                  "AOM_DSP_COMMON_INTRIN_SSSE3" "aom")
 
     if (CONFIG_AV1_ENCODER)
       if ("${AOM_TARGET_CPU}" STREQUAL "x86_64")
         list(APPEND AOM_DSP_ENCODER_ASM_SSSE3
              ${AOM_DSP_ENCODER_ASM_SSSE3_X86_64})
       endif ()
-      add_asm_library("aom_dsp_encoder_ssse3" "AOM_DSP_ENCODER_ASM_SSSE3"
-                      "aom_dsp")
+      add_asm_library("aom_dsp_encoder_ssse3" "AOM_DSP_ENCODER_ASM_SSSE3" "aom")
       if (AOM_DSP_ENCODER_INTRIN_SSSE3)
         add_intrinsics_object_library("-mssse3" "ssse3" "aom_dsp_encoder"
-                                      "AOM_DSP_ENCODER_INTRIN_SSSE3" "aom_dsp")
+                                      "AOM_DSP_ENCODER_INTRIN_SSSE3" "aom")
       endif ()
     endif ()
   endif ()
 
   if (HAVE_SSE4_1)
     add_intrinsics_object_library("-msse4.1" "sse4_1" "aom_dsp_common"
-                                  "AOM_DSP_COMMON_INTRIN_SSE4_1" "aom_dsp")
+                                  "AOM_DSP_COMMON_INTRIN_SSE4_1" "aom")
     if (CONFIG_AV1_ENCODER)
       if (AOM_DSP_ENCODER_INTRIN_SSE4_1)
         add_intrinsics_object_library("-msse4.1" "sse4_1" "aom_dsp_encoder"
-                                      "AOM_DSP_ENCODER_INTRIN_SSE4_1" "aom_dsp")
+                                      "AOM_DSP_ENCODER_INTRIN_SSE4_1" "aom")
       endif ()
       add_asm_library("aom_dsp_encoder_sse4_1" "AOM_DSP_ENCODER_ASM_SSE4_1"
-                      "aom_dsp")
+                      "aom")
     endif ()
   endif ()
 
   if (HAVE_AVX AND "${AOM_TARGET_CPU}" STREQUAL "x86_64")
     if (CONFIG_AV1_ENCODER)
       add_asm_library("aom_dsp_encoder_avx" "AOM_DSP_ENCODER_AVX_ASM_X86_64"
-                      "aom_dsp")
+                      "aom")
     endif ()
   endif ()
 
   if (HAVE_AVX2)
     add_intrinsics_object_library("-mavx2" "avx2" "aom_dsp_common"
-                                  "AOM_DSP_COMMON_INTRIN_AVX2" "aom_dsp")
+                                  "AOM_DSP_COMMON_INTRIN_AVX2" "aom")
     if (CONFIG_AV1_ENCODER)
       add_intrinsics_object_library("-mavx2" "avx2" "aom_dsp_encoder"
-                                    "AOM_DSP_ENCODER_INTRIN_AVX2" "aom_dsp")
+                                    "AOM_DSP_ENCODER_INTRIN_AVX2" "aom")
     endif ()
   endif ()
 
   if (HAVE_NEON_ASM)
     if (AOM_ADS2GAS_REQUIRED)
-      add_gas_asm_library("aom_dsp_common_neon" "AOM_DSP_COMMON_ASM_NEON"
-                          "aom_dsp")
+      add_gas_asm_library("aom_dsp_common_neon" "AOM_DSP_COMMON_ASM_NEON" "aom")
     else ()
-      add_asm_library("aom_dsp_common_neon" "AOM_DSP_COMMON_ASM_NEON" "aom_dsp")
+      add_asm_library("aom_dsp_common_neon" "AOM_DSP_COMMON_ASM_NEON" "aom")
     endif ()
   endif ()
 
   if (HAVE_NEON)
     add_intrinsics_object_library("${AOM_NEON_INTRIN_FLAG}" "neon"
                                   "aom_dsp_common" "AOM_DSP_COMMON_INTRIN_NEON"
-                                  "aom_dsp")
+                                  "aom")
   endif ()
 
   if (HAVE_DSPR2)
     add_intrinsics_object_library("" "dspr2" "aom_dsp_common"
-                                  "AOM_DSP_COMMON_INTRIN_DSPR2" "aom_dsp")
+                                  "AOM_DSP_COMMON_INTRIN_DSPR2" "aom")
   endif ()
 
   if (HAVE_MSA)
     add_intrinsics_object_library("" "msa" "aom_dsp_common"
-                                  "AOM_DSP_COMMON_INTRIN_MSA" "aom_dsp")
+                                  "AOM_DSP_COMMON_INTRIN_MSA" "aom")
     if (CONFIG_AV1_ENCODER)
       add_intrinsics_object_library("" "msa" "aom_dsp_encoder"
-                                    "AOM_DSP_ENCODER_INTRIN_MSA" "aom_dsp")
+                                    "AOM_DSP_ENCODER_INTRIN_MSA" "aom")
     endif ()
   endif ()
 
-  target_link_libraries(aom PRIVATE aom_dsp)
-
   # Pass the new lib targets up to the parent scope instance of
   # $AOM_LIB_TARGETS.
   set(AOM_LIB_TARGETS ${AOM_LIB_TARGETS} PARENT_SCOPE)