drm/xe: Fix build_pt_update_batch_sram for non-4K PAGE_SIZE

drm/xe: Fix build_pt_update_batch_sram for non-4K PAGE_SIZE

The build_pt_update_batch_sram function in the Xe migrate layer assumes
PAGE_SIZE == XE_PAGE_SIZE (4K), which is not a valid assumption on
non-x86 platforms. This patch updates build_pt_update_batch_sram to
correctly handle PAGE_SIZE > 4K by programming multiple 4K GPU pages per
CPU page.

v5:
 - Mask off non-address bits during compare

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Tested-by: Simon Richter <Simon.Richter@hogyros.de>
Reviewed-by: Stuart Summers <stuart.summers@intel.com>
Link: https://lore.kernel.org/r/20251013034555.4121168-2-matthew.brost@intel.com