avfilter/af_amerge: Free inpads' names generically

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

libavfilter/af_amerge.c

@@ -60,8 +60,6 @@ static av_cold void uninit(AVFilterContext *ctx)
     AMergeContext *s = ctx->priv;
 
     av_freep(&s->in);
-    for (unsigned i = 0; i < ctx->nb_inputs; i++)
-        av_freep(&ctx->input_pads[i].name);
 }
 
 static int query_formats(AVFilterContext *ctx)
@@ -328,10 +326,8 @@ static av_cold int init(AVFilterContext *ctx)
         };
         if (!name)
             return AVERROR(ENOMEM);
-        if ((ret = ff_append_inpad(ctx, &pad)) < 0) {
-            av_freep(&pad.name);
+        if ((ret = ff_append_inpad_free_name(ctx, &pad)) < 0)
             return ret;
-        }
     }
     return 0;
 }