fix for systems not defining PRIu64, not everyone knows C99.

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@4721 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavutil/common.h

@@ -104,6 +104,10 @@
 #   endif /* other OS */
 #endif /* EMULATE_INTTYPES */
 
+#ifndef PRIu64
+#define PRIu64 "lld"
+#endif
+
 #ifndef INT16_MIN
 #define INT16_MIN       (-0x7fff-1)
 #endif