drm/xe: Add event tracing for CTB

Event tracing enabled for CTB submissions.

Additional minor refactor - Removed a unnecessary ct_to_xe() call.

v2: Remove a unwanted comment (Hari)
    Add missing change to commit message

Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Reviewed-by: Haridhar Kalvala <haridhar.kalvala@intel.com>
Link: https://lore.kernel.org/intel-xe/20231019093140.1901665-2-balasubramani.vivekanandan@intel.com/


Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>