drm/xe: Convert xe_gem_fault to use direct xe_pm_runtime calls

drm/xe: Convert xe_gem_fault to use direct xe_pm_runtime calls

The gem page fault is one of the outer bound protections where
we want to ensure that the hardware is in D0 before proceeding
with memory access. Let's convert it towards the xe_pm_runtime
functions directly so we can then convert the mem_access to be
inner protection only and then Kill it for good.

Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240417203952.25503-6-rodrigo.vivi@intel.com
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>