MAINTAINERS: Add sound devicetree bindings for Wolfson Micro devices

Include all wm* sound bindings in the section for Wolfson Micro
drivers. This section already includes the actual driver source
files.

Also update the existing entry to match all wlf,* sound bindings.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20210727164948.4308-1-rf@opensource.cirrus.com


Signed-off-by: Mark Brown <broonie@kernel.org>