drm/i915/gt: Update engine_init_common documentation

Change the function doc to reflect updated name.

v2: un-kerneldoc the comment(Matt).
    :s/engines_init_common/engine_init_common(Andi)

Cc: Andi Shyti <andi.shyti@linux.intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230310101024.4700-1-nirmoy.das@intel.com