drm/xe: Add xe_guc_pagefault layer

drm/xe: Add xe_guc_pagefault layer

Add xe_guc_pagefault layer (producer) which parses G2H fault messages
messages into struct xe_pagefault, forwards them to the page fault layer
(consumer) for servicing, and provides a vfunc to acknowledge faults to
the GuC upon completion. Replace the old (and incorrect) GT page fault
layer with this new layer throughout the driver.

As part of this change, the ACC handling code has been removed, as it is
dead code that is currently unused.

v2:
 - Include engine instance (Stuart)

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Tested-by: Francois Dugast <francois.dugast@intel.com>
Link: https://patch.msgid.link/20251031165416.2871503-7-matthew.brost@intel.com