regulator: arizona-micsupp: Correct wm5110 voltage selection

wm5110 provides different voltage configurations than the other Arizona
parts, this patch adds support for this into the regulator driver. Also
fixup the default for the configuration register for wm5110.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org (v3.12)