power: supply: Support ROHM bd99954 charger

The ROHM BD99954 is a Battery Management LSI for 1-4 cell Lithium-Ion
secondary battery intended to be used in space-constraint equipment such
as Low profile Notebook PC, Tablets and other applications. BD99954
provides a Dual-source Battery Charger, two port BC1.2 detection and a
Battery Monitor.

Support ROHM BD99954 Charger IC.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>