virtio: console: open: Use a common path for error handling

Just re-arrange code for future patches.
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

drivers/char/virtio_console.c

@@ -711,6 +711,7 @@ static int port_fops_open(struct inode *inode, struct file *filp)
 {
 	struct cdev *cdev = inode->i_cdev;
 	struct port *port;
+	int ret;
 
 	port = container_of(cdev, struct port, cdev);
 	filp->private_data = port;
@@ -719,14 +720,17 @@ static int port_fops_open(struct inode *inode, struct file *filp)
 	 * Don't allow opening of console port devices -- that's done
 	 * via /dev/hvc
 	 */
-	if (is_console_port(port))
-		return -ENXIO;
+	if (is_console_port(port)) {
+		ret = -ENXIO;
+		goto out;
+	}
 
 	/* Allow only one process to open a particular port at a time */
 	spin_lock_irq(&port->inbuf_lock);
 	if (port->guest_connected) {
 		spin_unlock_irq(&port->inbuf_lock);
-		return -EMFILE;
+		ret = -EMFILE;
+		goto out;
 	}
 
 	port->guest_connected = true;
@@ -745,6 +749,8 @@ static int port_fops_open(struct inode *inode, struct file *filp)
 	send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
 
 	return 0;
+out:
+	return ret;
 }
 
 /*