Staging: asus_oled: fix oops in 2.6.32.2

After updating to 2.6.32 kernel, I started experiencing Oopses caused by
the asus_oled module. After quick investigation, I wrapped this simple
patch which fixes an Oops in by asus_oled module on 2.6.32.2 kernel,
caused by incorrect usage of strict_strtoul function call within
set_enabled and set_disabled functions. This can be triggered by simple
running the userspace client for asus_old (e.g., 'asusoled -e' or
'asusoled -d').

Signed-off-by: Eugeni Dodonov <eugeni@mandriva.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>