regulator: twl6030: add support for vdd1, vdd2 and vdd3 regulators

vdd1 and vdd2 are now common regulators for twl4030 and twl6030. Also
added vdd3 as a new regulator for twl6030. twl6030 vdd1...vdd3 smps
regulator voltages can only be controlled through the smartreflex
voltage channel, thus the support for the voltage_get and set is
minimal and requires external controller.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>