media: mediatek: vcodec: using each instance lat_buf count replace core ready list

Core Hardware decoder depends on each instance lat_buf count,
calling queue_work decode again when the lat_buf count of each instance
isn't zero.

Fixes: 365e4ba0 ("media: mtk-vcodec: Add work queue for core hardware decode")
Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

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

@@ -239,7 +239,7 @@ static void vdec_msg_queue_core_work(struct work_struct *work)
 	mtk_vcodec_dec_disable_hardware(ctx, MTK_VDEC_CORE);
 	vdec_msg_queue_qbuf(&ctx->msg_queue.lat_ctx, lat_buf);
 
-	if (!list_empty(&dev->msg_queue_core_ctx.ready_queue)) {
+	if (atomic_read(&lat_buf->ctx->msg_queue.core_list_cnt)) {
 		mtk_v4l2_debug(3, "re-schedule to decode for core: %d",
 			       dev->msg_queue_core_ctx.ready_num);
 		queue_work(dev->core_workqueue, &msg_queue->core_work);