mfd: arizona: Add MICVDD to mapped regulators

Currently, MICVDD only binds because it is both the regulator name and
the consumer name and we will always match against the regulator name
regardless of the consumer device. If the regulator was renamed using
the init_data ASoC will no longer be able to locate the supply, as it
will be looking on the CODEC device where as the MICVDD consumer is on
the Arizona device. Add a mapping as we do for the other regulators.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>