powerpc: 4xx: remove commented out Kconfig entries

These Kconfig entries have been commented out ever since commit f6557331
("[...] Re-organize Kconfig code for 4xx in arch/powerpc"). There's no
indication why they're commented out. It looks like they're just "old,
unused [...] config options" that were not removed, as other entries
were in that commit, but only commented out. They might as well be
removed now.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>