FreeBSD PVH guest support

[Roger Pau Monné]

Hello,

I've updated the branch one more time in order to cope with the recent
HEAD changes regarding SMAP parsing, as usual the branch can be found at:

http://xenbits.xen.org/gitweb/?p=people/royger/freebsd.git;a=shortlog;h=refs/heads/pvh_v5

Also, I've created a wiki page that describes how to set up a FreeBSD
PVH guest:

http://wiki.xen.org/wiki/FreeBSD_PVH

In case anyone wants to give it a try :)

Thanks.