avfilter/avfilter: Make ff_tlog_ref() static

It allows compilers to inline the one and only call to this function
in its caller or even to optimize it away completely (this function
is empty in case TRACE is not defined).

Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavfilter/avfilter.c

@@ -47,7 +47,7 @@
 #include "libavutil/ffversion.h"
 const char av_filter_ffversion[] = "FFmpeg version " FFMPEG_VERSION;
 
-void ff_tlog_ref(void *ctx, AVFrame *ref, int end)
+static void tlog_ref(void *ctx, AVFrame *ref, int end)
 {
     ff_tlog(ctx,
             "ref[%p buf:%p data:%p linesize[%d, %d, %d, %d] pts:%"PRId64" pos:%"PRId64,
@@ -1018,7 +1018,7 @@ fail:
 int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
 {
     int ret;
-    FF_TPRINTF_START(NULL, filter_frame); ff_tlog_link(NULL, link, 1); ff_tlog(NULL, " "); ff_tlog_ref(NULL, frame, 1);
+    FF_TPRINTF_START(NULL, filter_frame); ff_tlog_link(NULL, link, 1); ff_tlog(NULL, " "); tlog_ref(NULL, frame, 1);
 
     /* Consistency checks */
     if (link->type == AVMEDIA_TYPE_VIDEO) {

libavfilter/internal.h

@@ -230,8 +230,6 @@ void ff_command_queue_pop(AVFilterContext *filter);
 
 char *ff_get_ref_perms_string(char *buf, size_t buf_size, int perms);
 
-void ff_tlog_ref(void *ctx, AVFrame *ref, int end);
-
 void ff_tlog_link(void *ctx, AVFilterLink *link, int end);
 
 /**