drm/xe: use entry_dump callbacks for xe2+ PAT dumps

drm/xe: use entry_dump callbacks for xe2+ PAT dumps

Move xe2+ PAT entry printing into the entry_dump op so platform
specific logic stays localized, simplifying future maintenance.

v2:
 - Do not null xe->pat.ops for VFs.
 - Skip PAT init and dump on VFs (-EOPNOTSUPP), avoiding NULL ops use.

v3:
 - fixed typo

v4: (Matt)
 - Switch xe2_dump() to use the new ops->entry_dump() vfunc.
 - Remove xe3p_xpc_dump() and reuse the common xe2_dump() for Xe3p XPC.
 - This also fixes Xe3p_HPM media PAT dumping by using the proper
non-MCR access for the PAT register range (bspec 76445).

Cc: Matt Roper <matthew.d.roper@intel.com>
Suggested-by: Brian Nguyen <brian3.nguyen@intel.com>
Signed-off-by: Xin Wang <x.wang@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patch.msgid.link/20260130175349.2249033-1-x.wang@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>