MFD: DA9052/53 MFD core module

The DA9052/53 is a highly integrated PMIC subsystem with supply domain
flexibility to support wide range of high performance application.

It provides voltage regulators, GPIO controller, Touch Screen, RTC, Battery
control and other functionality.

This patch is functionally tested on Samsung SMDKV6410.

Signed-off-by: David Dajun Chen <dchen@diasemi.com>
Signed-off-by: Ashish Jangam <ashish.jangam@kpitcummins.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>