drm/xe: Do not wake device during a GT reset

Waking the device during a GT reset can lead to unintended memory
allocation, which is not allowed since GT resets occur in the reclaim
path. Prevent this by holding a PM reference while a reset is in flight.

Fixes: dd08ebf6 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: stable@vger.kernel.org
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://lore.kernel.org/r/20251022005538.828980-3-matthew.brost@intel.com


(cherry picked from commit 480b358e7d8ef69fd8f1b0cad6e07c7d70a36ee4)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>