regulator: hi6421v530: add driver for hi6421v530 voltage regulator

add the driver for hi6421v530 voltage regulator

Signed-off-by: Wang Xiaoyin <hw.wangxiaoyin@hisilicon.com>
Signed-off-by: Guodong Xu <guodong.xu@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
3 files changed