drm/xe/rtp: Prefer helper macros from xe_args.h

Some custom implementation can be replaced with generic macros
from the linux/args.h or xe_args.h.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240502223313.2527-4-michal.wajdeczko@intel.com