msm_mpdecision: add input event boost [read more]

This adds an input event boost to mpdecision.
It will basically boost the min freq of all cpus to predefined values if an
input event is detected.
Devices that qualify as boosters must fullfill one of these conditions:
- contain touch in their name
- contain keyboard in their name
This also boosts cpus independently from each other. Meaning:
If a cpu is hotplugged after the boost of another cpu was initiated the next
boost pulse will boost that cpu too.

Sysfs interface underway.

Signed-off-by: Dennis Rassmann <showp1984@gmail.com>