Char: vt_ioctl, fix BKL imbalance

Stanse found (again) a BKL imbalance in vt_ioctl.

It's easily triggerable by ioctl(dev_tty_fd, VT_SETACTIVATE, NULL);

Introduced by

commit d3b5cffc                                 Author: Alan Cox <alan@linux.intel.com>
Date:   Sat Sep 19 13:13:26 2009 -0700

    vt: add an activate and lock
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/char/vt_ioctl.c

@@ -981,8 +981,10 @@ int vt_ioctl(struct tty_struct *tty, struct file * file,
 			goto eperm;
 
 		if (copy_from_user(&vsa, (struct vt_setactivate __user *)arg,
-						sizeof(struct vt_setactivate)))
-			return -EFAULT;
+					sizeof(struct vt_setactivate))) {
+			ret = -EFAULT;
+			goto out;
+		}
 		if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES)
 			ret = -ENXIO;
 		else {