drm/xe/lrc: Add table with LRC layout

Add a table to document the LRC's BO layout to make it easier to
visualize how each region stacks on top of each other.

Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Link: https://lore.kernel.org/r/20250710-lrc-refactors-v2-4-a5e2ca03f6bd@intel.com


Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>