media: vivid: fix incorrect capabilities for radio

The vivid driver has two custom controls that change the behavior of RDS.
Depending on the control setting the V4L2_CAP_READWRITE capability is toggled.
However, after an earlier commit the capability was no longer set correctly.
This is now fixed.

Fixes: 9765a32c ("vivid: set device_caps in video_device")
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/vivid/vivid-ctrls.c

@@ -1196,6 +1196,7 @@ static int vivid_radio_rx_s_ctrl(struct v4l2_ctrl *ctrl)
 		v4l2_ctrl_activate(dev->radio_rx_rds_ta, dev->radio_rx_rds_controls);
 		v4l2_ctrl_activate(dev->radio_rx_rds_tp, dev->radio_rx_rds_controls);
 		v4l2_ctrl_activate(dev->radio_rx_rds_ms, dev->radio_rx_rds_controls);
+		dev->radio_rx_dev.device_caps = dev->radio_rx_caps;
 		break;
 	case V4L2_CID_RDS_RECEPTION:
 		dev->radio_rx_rds_enabled = ctrl->val;
@@ -1270,6 +1271,7 @@ static int vivid_radio_tx_s_ctrl(struct v4l2_ctrl *ctrl)
 		dev->radio_tx_caps &= ~V4L2_CAP_READWRITE;
 		if (!dev->radio_tx_rds_controls)
 			dev->radio_tx_caps |= V4L2_CAP_READWRITE;
+		dev->radio_tx_dev.device_caps = dev->radio_tx_caps;
 		break;
 	case V4L2_CID_RDS_TX_PTY:
 		if (dev->radio_rx_rds_controls)