ASoC: cs4270: enable regulators at probe time

Enable the bulk regulators at probe time so we can safely disable them
again when going to suspend without confusing the reference counter.

Signed-off-by: Daniel Mack <daniel@caiaq.de>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>