drm/i915/guc: Add preemption action to GuC firmware interface

drm/i915/guc: Add preemption action to GuC firmware interface

We're using GuC action to request preemption. However, after requesting
preemption we need to wait for GuC to finish its own post-processing
before we start submitting our requests. Firmware is using shared
context to report its status.
Let's update GuC firmware interface with those new definitions.

v2: Drop unused INTEL_GUC_PREEMPT_OPTION_IMMEDIATE

Signed-off-by: Michał Winiarski <[email protected]>
Cc: Jeff McGee <[email protected]>
Cc: Michal Wajdeczko <[email protected]>
Cc: Oscar Mateo <[email protected]>
Reviewed-by: Jeff McGee <[email protected]>
Signed-off-by: Chris Wilson <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]