[PATCH] ppc64: improve g5 sound headphone mute

This patch fixes a couple more issues with the management of the GPIOs
dealing with headphone and line out mute on the G5.  It should fix the
remaining problems of people not getting any sound out of the headphone
jack.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>