staging: wilc1000: change return type to 'void' for lock init & deinit functions

Cleanup patch to use 'void' return type for wlan_deinit_locks() &
wlan_init_locks(), as same value is return.

Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>