drm/xe: Return NULL in case of drmm_add_action_or_reset failure

drm/xe: Return NULL in case of drmm_add_action_or_reset failure

In case of drmm_add_action_or_reset failure return NULL and no need
to print warning messages as they will be printed implictly.

Cc: Tejas Upadhyay <tejas.upadhyay@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240412181211.1155732-5-himal.prasad.ghimiray@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>