drm/xe: Move PTE/PDE bit definitions to proper header

We already have dedicated header for GGTT/PPGTT definitions.
It's also cleaner to separate them from implementation macros.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Acked-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240405123520.847-1-michal.wajdeczko@intel.com