LP3971 PMIC regulator driver (updated and combined version)

This patch adds regulator drivers for National Semiconductors LP3971 PMIC.
This LP3971 PMIC controller has 3 DC/DC voltage converters and 5 low
drop-out (LDO) regulators. LP3971 PMIC controller uses I2C interface.

Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index faf7bcc..4d762c4 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -9,6 +9,7 @@
 obj-$(CONFIG_REGULATOR_USERSPACE_CONSUMER) += userspace-consumer.o
 
 obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o
+obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o
 obj-$(CONFIG_REGULATOR_MAX1586) += max1586.o
 obj-$(CONFIG_REGULATOR_TWL4030) += twl4030-regulator.o
 obj-$(CONFIG_REGULATOR_WM8350) += wm8350-regulator.o