i915/guc: Add Kabylake GuC Loading

This patch added the loading of the GuC for Kabylake.
It loads a 9.14 firmware.

v2: Fix commit message
v3: Fix major/minor var names to match -nightly. (Rodrigo)

Cc: Christophe Prigent <christophe.prigent@intel.com>
Signed-off-by: Peter Antoine <peter.antoine@intel.com>
Signed-off-by: Michel Thierry <michel.thierry@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com> (v3)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1467304672-2106-1-git-send-email-rodrigo.vivi@intel.com