[PATCH 0/18 V2]: PVH changes for xen

[Mukesh Rathor <mukesh.rathor@oracle.com>]

Finally, I've version 2 of my patches for PVH for xen (Linux patches
have been previously submitted). This is Phase I.  These patches are built
on top of git c/s: 65c9792df60051b5f5eaadbc47a118cfba7edd49

Phase I:
   - Establish a baseline of something working. These patches allow for 
     dom0 to be booted in PVH mode, and after that guests to be started
     in PV, PVH, and HVM modes. I also tested booting dom0 in PV mode,
     and starting PV, PVH, and HVM guests.

     There are few fixme's that I thought we could punt to Phase II. 

     Also, the disk must be specified as phy: in vm.cfg file:
         > losetup /dev/loop1 guest.img
         > vm.cfg file: disk = ['phy:/dev/loop1,xvda,w']  

     I've not tested anything else.

Phase II:
   - AMD port. 
   - Linux MSI-x fixup, see xen-devel thread "[PVH]: Help: msi.c".
   - fine tune shutdown path. I need to look at shutdown path during 
     dom0 reboot and go thru the cleanup code again upon shutdown.
   - arch_get_info_guest() and few other fixmes.
   - Change xl to support other modes other than "phy:".

Phase III:
   - VTSC support for PVH.
   - Migration, shadow code. I've skipped shadow code for now.

Thanks for all the help,
Mukesh