lavc/hevcdec: call ff_thread_finish_setup() even if hwaccel is in use

Serializing frame threading for non-threadsafe hwaccels is handled at the
generic level, the decoder does not need to care about it.

libavcodec/hevc/hevcdec.c

@@ -3029,8 +3029,9 @@ static int hevc_frame_start(HEVCContext *s)
         ret = FF_HW_CALL(s->avctx, start_frame, NULL, 0);
         if (ret < 0)
             goto fail;
-    } else
-        ff_thread_finish_setup(s->avctx);
+    }
+
+    ff_thread_finish_setup(s->avctx);
 
     return 0;