regmap: Updates for v4.4
Quite a few new features for regmap this time, mostly expanding things
around the edges of the existing functionality to cover more devices
rather than thinsg with wide applicability:
- Support for offload of the update_bits() operation to hardware where
devices implement bit level access.
- Support for a few extra operations that need scratch buffers on
fast_io devices where we can't sleep.
- Expanded the feature set of regmap_irq to cope with some extra
register layouts.
- Cleanups to the debugfs code.
Merge remote-tracking branches 'regmap/topic/atomic', 'regmap/topic/debugfs' and 'regmap/topic/irq-hdr' into regmap-next
