From: Ashok Raj <ashok.raj@intel.com>

Supports basic ability to enable hotplug functions for IA64.
Code is just evolving, and there are several loose ends to tie up.

What this code drop does
- Support logical online and offline
- Handles interrupt migration without loss of interrupts.
- Handles stress fine > 24+ hrs with make -j/ftp/rcp workloads
- Handles irq migration from a dying cpu without loss of interrupts.

What needs to be done
- Boot CPU removal support, with platform level authentication
- Putting cpu being removed in BOOT_RENDEZ mode.