CRIS: gpio: don't call copy_to_user()/copy_from_user() while holding spinlocks

copy_to_user()/copy_from_user() must not be used with spinlocks held.
Move locks inside each case so we have better control of when the locks
are held.

Also, since we use spinlocks, we don't need to hold the BKL, so remove it.

Reported-by: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: Jesper Nilsson <jesper.nilsson@axis.com>