drm/i915/guc: Simplify programming of GUC_SHIM_CONTROL

drm/i915/guc: Simplify programming of GUC_SHIM_CONTROL

We can program GUC_SHIM_CONTROL register with all expected
bits without use of extra macro defined in fwif.h

v2: rebased without pre-prod code
v3: fixed typo

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Reviewed-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171103151816.62048-4-michal.wajdeczko@intel.com
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>