[PATCH] aoa: i2sbus: fix for PowerMac7,2 and 7,3

This patch cleans up the resource handling in i2sbus and adds workarounds for
the broken device trees on the PowerMac7,2 and 7,3.  Some of this code will
later move again when macio_asic is going to export all the sub-nodes too.

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