Silence one icc warning:

variable "..." is used before its value is set


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@17127 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavutil/common.h

@@ -102,7 +102,7 @@
 #endif
 
 #ifndef av_uninit
-#if defined(__GNUC__)
+#if defined(__GNUC__) && !defined(__ICC)
 #    define av_uninit(x) x=x
 #else
 #    define av_uninit(x) x