ff_gcd is already in libavutil/common.h, no need for an extra prototype here

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@23643 b3059339-0415-0410-9bf9-f77b7e298cf2

libaf/af_lavcresample.c

@@ -17,8 +17,6 @@
 #include "rational.h"
 #endif
 
-int64_t ff_gcd(int64_t a, int64_t b);
-
 // Data for specific instances of this filter
 typedef struct af_resample_s{
     struct AVResampleContext *avrctx;