sound: sdw: Add hw_params to SoundWire config helper function

The vast majority of the current users of the SoundWire framework
have almost identical code for converting from hw_params to SoundWire
configuration. Whilst complex devices might require more, it is very
likely that most new devices will follow the same pattern. Save a
little code by factoring this out into a helper function.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20221123165432.594972-1-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>