This patch fixes the initialisation and reset of the tas codec.  The tas will
often reset if the i2s clocks go away so it needs to be completely
re-initialised when clocks come back.

Also, this patch adds some code for DRC that will be exploited later to add a
DRC control again, fixing a regression over snd-powermac.
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>