[PATCH] Add support for type argument in PAL_GET_PSTATE

PAL_GET_PSTATE accepts a type argument to return different kinds of
frequency information.
Refer: Intel Itanium®Architecture Software Developer's Manual -
Volume 2: System Architecture, Revision 2.2
(http://developer.intel.com/design/itanium/manuals/245318.htm)

Add the support for type argument and use Instantaneous frequency
in the acpi driver.

Also fix a bug, where in return value of PAL_GET_PSTATE was getting compared
with 'control' bits instead of 'status' bits.

Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>