ASoC: codecs: wcd939x-sdw: use devres for regmap allocation

ASoC: codecs: wcd939x-sdw: use devres for regmap allocation

Components are bound inside a new devres group so that any resources
allocated can be released on bind failure and on unbind without
affecting anything else.

Switch to using device managed regmap allocation for consistency while
dropping the misleading comment claiming that devres cannot be used.

Cc: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20251201092259.11761-1-johan@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>