bitkeeper revision 1.1780 (42c3a8c4tqEOpGy663gWO35k5QwZTw)

bitkeeper revision 1.1780 (42c3a8c4tqEOpGy663gWO35k5QwZTw)

[PATCH] Infrastructure for interrupt handling.

Infrastructure for interrupt handling.

- support interruptibility
- handle interrupt window exiting control appropriately
- Add ioapic device models imported from Bochs under LGPL
- generalize the interrupt architecture to support both PIC/APIC

This patch is necessary to fix several bugs on 32 bit VMX and prepares the
ground for adding a local APIC device model in the hypervisor.

Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Eddie Dong <eddie.dong@intel.com>
Signed-off-by: Arun Sharma <arun.sharma@intel.com>