drm/xe: Fix unexpected backmerge results

The recent backmerge from drm-next to drm-xe-next brought with it
some silent unexpected results. One code snippet was added twice
and a partial revert had merge errors. Fix that up to
reinstate the affected code as it was before the backmerge.

v2:
- Commit log message rewording (Lucas DeMarchi)

Fixes: 79790b68

 ("Merge drm/drm-next into drm-xe-next")
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240423121114.39325-1-thomas.hellstrom@linux.intel.com