drm/xe: Update register definitions in LRC layout header

drm/xe: Update register definitions in LRC layout header

Update the register definitions in xe_lrc_layout.h to align with the
official hardware specification (Bspec) terminology. Specifically:

- rename PVC_CTX_ACC_CTR_THOLD to CTX_ACC_CTR_THOLD
- rename PVC_CTX_ASID to CTX_ASID

Signed-off-by: Xin Wang <x.wang@intel.com>
Reviewed-by: Stuart Summers <stuart.summers@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20250711060924.7373-1-x.wang@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>