drm/xe/migrate: Fix number of PT structs in docbook

Update xe_migrate_doc.h with 32 page table structs (not 48)

v2: minor typo fix
Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20230306133459.7803-1-niranjana.vishwanathapura@intel.comSigned-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

drivers/gpu/drm/xe/xe_migrate_doc.h

@@ -21,7 +21,7 @@
  * table BOs for updates, and identity map the entire device's VRAM with 1 GB
  * pages.
  *
- * Currently the page structure consists of 48 phyiscal pages with 16 being
+ * Currently the page structure consists of 32 physical pages with 16 being
  * reserved for BO mapping during copies and clear, 1 reserved for kernel binds,
  * several pages are needed to setup the identity mappings (exact number based
  * on how many bits of address space the device has), and the rest are reserved