Add support for CS35L63 Smart Amplifier

Merge series from Stefan Binding <sbinding@opensource.cirrus.com>:

CS35L63 is a Mono Class-D PC Smart Amplifier, with Speaker Protection
and Audio Enhancement Algorithms.

CS35L63 uses a similar control interface to CS35L56 so support for
it can be added into the CS35L56 driver.
CS35L63 only has SoundWire and I2C control interfaces.