regulator: Updates for v3.10 The diffstat and changelog here is dominated by Lee Jones' heroic efforts to sync the ab8500 driver that's been maintained out of tree with mainline (plus Axel's cleanup work on the results) but there's a few other things here: - Axel Lin added regulator_map_voltage_ascend() optimising a common pattern for drivers using the core code. - Milo Kim tought the regulator core to handle regulators sharing an enable GPIO, avoiding the need to do hacks to support such systems. - Andrew Bresticker added code to handle missing supplies for regulators more sensibly for device tree systems, reducing the need for stubbing there. plus the usual batch of driver specific updates and fixes.