x86: Add hardware_subarch ID for Moorestown

x86 bootprotocol 2.07 has introduced hardware_subarch ID in the boot
parameters provided by FW. We use it to identify Moorestown platforms.

[ tglx: Cleanup and paravirt fix ]

Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>