Remove CONFIG_{DE,EN}CODERS from the CMake build.

Use CONFIG_AV1_{DE,EN}CODER to control decoder and
encoder support inclusion instead.

BUG=aomedia:76,aomedia:508

Change-Id: Ib150ae382b301885589f30d9b6e98d3bfdd1afce
diff --git a/tools_common.h b/tools_common.h
index 8acb370..4bf7fd0 100644
--- a/tools_common.h
+++ b/tools_common.h
@@ -19,7 +19,7 @@
 #include "aom/aom_integer.h"
 #include "aom_ports/msvc.h"
 
-#if CONFIG_ENCODERS
+#if CONFIG_AV1_ENCODER
 #include "./y4minput.h"
 #endif
 
@@ -100,7 +100,7 @@
   int only_i420;
   uint32_t fourcc;
   struct AvxRational framerate;
-#if CONFIG_ENCODERS
+#if CONFIG_AV1_ENCODER
   y4m_input y4m;
 #endif
 };