uboot-imx

power: pmic: Palmas: Add the base pmic support

Add support to bind the regulators/child nodes with the pmic.
Also adds the pmic i2c based read/write funtions to access pmic
registers.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>