drm/xe/xe_pci_error: Group all devres to release them on PCIe slot reset

drm/xe/xe_pci_error: Group all devres to release them on PCIe slot reset

Add devres grouping to handle device resource cleanup during
PCI error recovery.

Secondary Bus Reset (SBR) is triggered by PCI core when the
error_detected/mmio_enabled callbacks return PCI_ERS_RESULT_NEED_RESET.

Once SBR is complete, the slot_reset callback is triggered. SBR wipes
out all device memory requiring XE KMD to perform a device removal and
reprobe.
Calling xe_pci_remove() alone does not free the devres allocated.
Since there are no exported functions to release all devres, group the
devres allocations and release the entire group during slot reset to
ensure proper cleanup.

Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Mallesh Koujalagi <mallesh.koujalagi@intel.com>
Link: https://patch.msgid.link/20260629082802.3690896-8-riana.tauro@intel.com
Signed-off-by: Riana Tauro <riana.tauro@intel.com>