Intelli-Plug: Add sysfs toggle for screen-on-hotplug enable/disable

Multi-Core CPUs are meant for working with all cores and are optimized for balanced power consumption.
Example:

 - A Dual-Core CPU running with both cores each at 400mhz needs less power than a Dual-Core CPU running only one core at 800mhz!
 - Turning the secondary cores constantly on/off alse needs more power than saving it.

We only allow CPU1 to be turned off when device goes into suspend.
This is better way than using 'Dynamic Hotplug' which doesn't handle big tasks requesting the CPU, so all tasks have to be handled by one cor

This new function can be toggled by userspace entry 'int_hotplug'
Intelli-Plug: Disable Dual-Core mode

We get slightley better performance with normal mode without loosing more battery