drm/i915/icl: Add configuring MOCS in new Icelake engines

In Icelake, there are more engines on which Memory Object Control
States need to be configured. Besides adding Icelake under Skylake
config, the patch makes sure MOCS register addresses for the new
engines are properly defined.

Additional patch might be need later, in case the specification will
propose different MOCS config values for Icelake than in previous
gens.

v2: Restricted comments to gen11, updated description, renamed
defines.

v3: Used proper engine indexes for gen11.

v4: Ensure patch is Icelake only.

v5: Style fixes (proposed by mwajdeczko)

v6 (from Paulo): fix checkpatch's COMMIT_LOG_LONG_LINE (Checkpatch).

BSpec: 19405
BSpec: 21140
Cc: Oscar Mateo Lozano <oscar.mateo@intel.com>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Michel Thierry <michel.thierry@intel.com>
Signed-off-by: Tomasz Lis <tomasz.lis@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180502223142.3891-1-paulo.r.zanoni@intel.com