regulator: add new lp8788 regulator driver

TI LP8788 PMU has 4 BUCKS and 22 LDOs.
The voltage of BUCK1 and BUCK2 can be controlled by external gpios.
And some LDOs also can be enabled by external gpios.
The regmap interface is used for regulator operations.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 3923a3b..f34c3be 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -239,6 +239,12 @@
 	help
 	  This driver supports LP8720/LP8725 PMIC
 
+config REGULATOR_LP8788
+	bool "TI LP8788 Power Regulators"
+	depends on MFD_LP8788
+	help
+	  This driver supports LP8788 voltage regulator chip.
+
 config REGULATOR_PCF50633
 	tristate "NXP PCF50633 regulator driver"
         depends on MFD_PCF50633