Icc does not support attribute flatten, do not try to use it.

Originally committed as revision 19286 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavutil/common.h

@@ -82,7 +82,7 @@
 #endif
 
 #ifndef av_flatten
-#if AV_GCC_VERSION_AT_LEAST(4,1)
+#if (!defined(__ICC) || __ICC > 1110) && AV_GCC_VERSION_AT_LEAST(4,1)
 #    define av_flatten __attribute__((flatten))
 #else
 #    define av_flatten