regulator: cpr3-mmss-regulator: add support for msmcobalt CPR4 controller

Add support for the fuse layout and hardware constraints of the
msmcobalt CPR4 controller which is used to manage the GPU supply
regulator.  Also update the cpr3-regulator core driver in order
to support CPR register writing for this device.

Change-Id: I408854a93e820c168551bcfec7d4f87cdbe5d638
CRs-Fixed: 986619
Signed-off-by: David Collins <collinsd@codeaurora.org>