drm/xe/display: Mark dpt and related vma as uncached

Mark dpt and related vma as uncached to avoid pipe faults on some devices.

Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240318201850.127785-1-juhapekka.heikkila@gmail.com