lavfi/qsvvpp: change the output frame's width and height

Make sure the size of the output frame always matches the agreed upon
image size.

Signed-off-by: Wenbin Chen <wenbin.chen@intel.com>

libavfilter/qsvvpp.c

@@ -487,15 +487,14 @@ static QSVFrame *query_frame(QSVVPPContext *s, AVFilterLink *outlink)
         if (!out_frame->frame)
             return NULL;
 
-        out_frame->frame->width  = outlink->w;
-        out_frame->frame->height = outlink->h;
-
         ret = map_frame_to_surface(out_frame->frame,
                                    &out_frame->surface);
         if (ret < 0)
             return NULL;
     }
 
+    out_frame->frame->width  = outlink->w;
+    out_frame->frame->height = outlink->h;
     out_frame->surface.Info = s->vpp_param.vpp.Out;
 
     return out_frame;