drm/xe: Rename gt_init sub-functions

drm/xe: Rename gt_init sub-functions

s/gt_fw_domain_init/gt_init_with_gt_forcewake()/
s/all_fw_domain_init/gt_init_with_all_forcewake()/

Clarify that the functions are the part of gt_init() that are called
with the respective power domains held. all_domain() of course only
works after discovering and initialisation of force_wake on all engines,
that's why the split is needed in the first place.

Suggested-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20250619104858.418440-19-dev@lankhorst.se
Signed-off-by: Maarten Lankhorst <dev@lankhorst.se>