cpufreq: enable sibling cpu policy sharing
+ Cpufreq: create/remove percpu sysfs nodes once
thanks to faux123:
https://github.com/faux123/moto_x/commit/231111634e9377c0d6ee17a1c351988b0e0c1948
https://github.com/faux123/moto_x/commit/3d5ca6abfa478a273603385333d674f75f8c18e6
m7: ondemand: add multi-phase scaling from HTC

Change-Id: I8304006d4321b242a830b0d49e206220b52e7acc

Conflicts:
	drivers/cpufreq/cpufreq_ondemand.c