drm/xe: Removing extra mem_access protection from runtime pm

This is not needed any longer, now that we have all the protection
in place with the runtime pm itself.

Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240417203952.25503-7-rodrigo.vivi@intel.com


Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>