[media] s5p-mfc-dec: Don't use encoder stop command

The decoder should handle V4L2_DEC_CMD_STOP to trigger drain,
but it currently expecting V4L2_ENC_CMD_STOP.

Signed-off-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Acked-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/platform/s5p-mfc/s5p_mfc_dec.c

@@ -813,7 +813,7 @@ static int vidioc_decoder_cmd(struct file *file, void *priv,
 	unsigned long flags;
 
 	switch (cmd->cmd) {
-	case V4L2_ENC_CMD_STOP:
+	case V4L2_DEC_CMD_STOP:
 		if (cmd->flags != 0)
 			return -EINVAL;