[PATCH 1/4] regmap: sdw: move to -EOPNOTSUPP

[Pierre-Louis Bossart]

> If you want to change this you'd need to change it over the whole
> subsystem (if not other subsystems), including the places where the
> value is used.

ok, I'll drop this patch for now, keep -ENOTSUPP and deal with this 
later. The only thing I really care about for now is SoundWire MBQ 
support, this is the only thing gating SDCA contributions.