media: mediatek: vcodec: Can't set dst buffer to done when lat decode error

Core thread will call v4l2_m2m_buf_done to set dst buffer done for
lat architecture. If lat call v4l2_m2m_buf_done_and_job_finish to
free dst buffer when lat decode error, core thread will access kernel
NULL pointer dereference, then crash.
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/mediatek/vcodec/mtk_vcodec_dec_stateless.c

@@ -253,7 +253,7 @@ static void mtk_vdec_worker(struct work_struct *work)
 
 	state = ret ? VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE;
 	if (!IS_VDEC_LAT_ARCH(dev->vdec_pdata->hw_arch) ||
-	    ctx->current_codec == V4L2_PIX_FMT_VP8_FRAME || ret) {
+	    ctx->current_codec == V4L2_PIX_FMT_VP8_FRAME) {
 		v4l2_m2m_buf_done_and_job_finish(dev->m2m_dev_dec, ctx->m2m_ctx, state);
 		if (src_buf_req)
 			v4l2_ctrl_request_complete(src_buf_req, &ctx->ctrl_hdl);