kill warning

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@5588 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavcodec/i386/mpegvideo_mmx_template.c

@@ -19,6 +19,7 @@
  */
 #undef SPREADW
 #undef PMAXW
+#undef PMAX
 #ifdef HAVE_MMX2
 #define SPREADW(a) "pshufw $0, " #a ", " #a " \n\t"
 #define PMAXW(a,b) "pmaxsw " #a ", " #b "     \n\t"