PM Core for OMAP1 platforms.

PM Core provides arch dependent routine to create/get/set operating points,
hooks up with arhc independent PowerOP layer and utilizes
clock/voltage framework to access hardware. PM Core is expected
to handle arch specific actions required to take place in case of
simultaneous coupled clocks/voltage change (for example  what
has to happen first) as well.

Current implementation relies on "smart" virtual mpu clock
introduced by OMAP1 clock framework (#define
PM_CORE_USE_MPU_CLOCK) but implementation for more
common case is presented for reference as well in #else branch
for PM_CORE_USE_MPU_CLOCK macro.

Since voltage framework is not merged into mainline yet
routine to change voltage is temporary implemented in the
PM Core for reference.

Please note that PM Core implementation is far incomplete
and servers mainly reference and proof of concept purpose for
the time being  (yes, I know parsing implementation is ugly ;).