usb: typec: altmodes/displayport: Drop the device reference in dp_altmode_probe()

In error paths, call typec_altmode_put_plug() to drop the device reference
obtained by typec_altmode_get_plug().

Fixes: 71ba4fe56656 ("usb: typec: altmodes/displayport: add SOP' support")
Cc: stable <[e-mail]>
Signed-off-by: Haoxiang Li <[e-mail]>
Reviewed-by: Heikki Krogerus <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/typec/altmodes/displayport.c

···
 	if (!(DP_CAP_PIN_ASSIGN_DFP_D(port->vdo) &
 	      DP_CAP_PIN_ASSIGN_UFP_D(alt->vdo)) &&
 	    !(DP_CAP_PIN_ASSIGN_UFP_D(port->vdo) &
-	      DP_CAP_PIN_ASSIGN_DFP_D(alt->vdo)))
+	      DP_CAP_PIN_ASSIGN_DFP_D(alt->vdo))) {
+		typec_altmode_put_plug(plug);
 		return -ENODEV;
+	}
 
 	dp = devm_kzalloc(&alt->dev, sizeof(*dp), GFP_KERNEL);
-	if (!dp)
+	if (!dp) {
+		typec_altmode_put_plug(plug);
 		return -ENOMEM;
+	}
 
 	INIT_WORK(&dp->work, dp_altmode_work);
 	mutex_init(&dp->lock);