staging: most: change type of access_ref

This patch changes the type of the access reference from atomit_t to int.
It is needed, because the reference variable is secured by synchronization
locks and does not need to be atomic anymore.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>