Expand SoundWire MBQ register map support

Merge series from Charles Keepax <ckeepax@opensource.cirrus.com>:

The current SDCA MBQ (Multi-Byte Quantities) register map only
supports 16-bit types, add support for more sizes and then update
the rt722 driver to use the new support. We also add support for
the deferring feature of MBQs to allow hardware to indicate it is
not currently ready to service a read/write.

Afraid I don't have hardware to test the rt722 change so it is
only build tested, but I thought it good to include a change to
demonstrate the new features in use.