rename -vfilters cli option to -vf in ffplay as well

Originally committed as revision 23104 to svn://svn.ffmpeg.org/ffmpeg/trunk

ffplay.c

@@ -3045,7 +3045,7 @@ static const OptionDef options[] = {
     { "framedrop", OPT_BOOL | OPT_EXPERT, {(void*)&framedrop}, "drop frames when cpu is too slow", "" },
     { "window_title", OPT_STRING | HAS_ARG, {(void*)&window_title}, "set window title", "window title" },
 #if CONFIG_AVFILTER
-    { "vfilters", OPT_STRING | HAS_ARG, {(void*)&vfilters}, "video filters", "filter list" },
+    { "vf", OPT_STRING | HAS_ARG, {(void*)&vfilters}, "video filters", "filter list" },
 #endif
     { "rdftspeed", OPT_INT | HAS_ARG| OPT_AUDIO | OPT_EXPERT, {(void*)&rdftspeed}, "rdft speed", "msecs" },
     { "default", OPT_FUNC2 | HAS_ARG | OPT_AUDIO | OPT_VIDEO | OPT_EXPERT, {(void*)opt_default}, "generic catch all option", "" },