avcodec/dxa: Cleanup generically after init failure

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

libavcodec/dxa.c

@@ -343,7 +343,6 @@ static av_cold int decode_init(AVCodecContext *avctx)
     c->dsize = avctx->width * avctx->height * 2;
     c->decomp_buf = av_malloc(c->dsize + DECOMP_BUF_PADDING);
     if (!c->decomp_buf) {
-        av_frame_free(&c->prev);
         av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
         return AVERROR(ENOMEM);
     }
@@ -371,4 +370,5 @@ AVCodec ff_dxa_decoder = {
     .close          = decode_end,
     .decode         = decode_frame,
     .capabilities   = AV_CODEC_CAP_DR1,
+    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
 };