Fix ndk build.

Android.mk should depend on vpx_dsp_rtcd.h

Change-Id: Ib614af195a9574fd849c28b695f9f4b3b2bd125c

build/make/Android.mk

diff --git a/build/make/Android.mk b/build/make/Android.mk
index 20f670a..0add523 100644
--- a/build/make/Android.mk
+++ b/build/make/Android.mk
@@ -170,6 +170,7 @@
 $(foreach file, $(LOCAL_SRC_FILES), $(LOCAL_PATH)/$(file)): vp9_rtcd.h
 endif
 $(foreach file, $(LOCAL_SRC_FILES), $(LOCAL_PATH)/$(file)): vpx_scale_rtcd.h
+$(foreach file, $(LOCAL_SRC_FILES), $(LOCAL_PATH)/$(file)): vpx_dsp_rtcd.h
 
 ifeq ($(TARGET_ARCH_ABI),x86)
 $(foreach file, $(LOCAL_SRC_FILES), $(LOCAL_PATH)/$(file)): vpx_config.asm