Add support to bind the regulators/child nodes with the pmic.
Also adds the pmic i2c based read/write functions to access pmic
registers.
Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
