[PULL][Utopic] GICv3 backport

[Dann Frazier]

hey,
 Some new ARM platforms will require GICv3 support, but the patches
didn't land upstream until the 3.17 window. This branch includes a
backport to utopic's 3.16:

  git://kernel.ubuntu.com/dannf/ubuntu-utopic-hyperscale.git gicv3

These patches include a refactoring of the existing GICv2 driver, so
I've regression tested on both a physical GICv2 system and with a
GICv2-based KVM guest. I verified the GICv3 support on a simulated
system.