avutil/dict: Deduplicate freeing dictionary

Reviewed-by: epirat07@gmail.com
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavutil/dict.c

@@ -145,11 +145,8 @@ int av_dict_set(AVDictionary **pm, const char *key, const char *value,
         m->elems[m->count].value = copy_value;
         m->count++;
     } else {
-        if (!m->count) {
-            av_freep(&m->elems);
-            av_freep(pm);
-        }
-        av_freep(&copy_key);
+        err = 0;
+        goto end;
     }
 
     return 0;
@@ -157,12 +154,13 @@ int av_dict_set(AVDictionary **pm, const char *key, const char *value,
 enomem:
     err = AVERROR(ENOMEM);
 err_out:
+    av_free(copy_value);
+end:
     if (m && !m->count) {
         av_freep(&m->elems);
         av_freep(pm);
     }
     av_free(copy_key);
-    av_free(copy_value);
     return err;
 }