ASoC: wm8804: Fix small issues in probe error paths

This patch fixes some small issues on the probe error paths. Firstly,
fail probe if we can't register the regulator notifiers as this
will cause the cache to never be synchronised which will result in odd
behaviour if the regulators are controllable. Secondly, we don't need to
call regulator_bulk_disable if the enable fails, because the regulator
core will handle this clean up for us. Finally, we need to disable the
regulators if snd_soc_register_codecs fails.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>