regulator: Updates for v3.16 The bulk of the changes for this release are a few new drivers however there are a couple of noticable core changes and the usual stream of cleanups and fixes: - Move disable of unused regulators later in init so it comes after deferred probe has iterated making startup smoother. - Fixes reference counting of the DT nodes for constraints from Charles Keepax. This has little practical impact since all real users of the regulator bindings use FDT which doesn't need the reference counting. - Lots of cleanups, especially to the Samsung drivers. - Support for Linear Technologies LTC3589, Texas Instruments TPS658640 and X-Powers AXP20x.