avfilter/af_anequalizer: Fix memleak when inserting pad fails

It has been forgotten to free the name of the second outpad if attaching
the first one to the AVFilterContext fails. Fixing this is easy: Only
prepare the second outpad after (and if) the first outpad has been
successfully attached to the AVFilterContext.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

libavfilter/af_anequalizer.c

@@ -199,6 +199,12 @@ static av_cold int init(AVFilterContext *ctx)
     if (!pad.name)
         return AVERROR(ENOMEM);
 
+    ret = ff_insert_outpad(ctx, 0, &pad);
+    if (ret < 0) {
+        av_freep(&pad.name);
+        return ret;
+    }
+
     if (s->draw_curves) {
         vpad = (AVFilterPad){
             .name         = av_strdup("out1"),
@@ -206,18 +212,8 @@ static av_cold int init(AVFilterContext *ctx)
             .config_props = config_video,
         };
         if (!vpad.name) {
-            av_freep(&pad.name);
             return AVERROR(ENOMEM);
         }
-    }
-
-    ret = ff_insert_outpad(ctx, 0, &pad);
-    if (ret < 0) {
-        av_freep(&pad.name);
-        return ret;
-    }
-
-    if (s->draw_curves) {
         ret = ff_insert_outpad(ctx, 1, &vpad);
         if (ret < 0) {
             av_freep(&vpad.name);