ASoC: wm8960: Fix error handling in probe

ASoC: wm8960: Fix error handling in probe

Commit 422f10adc3eb ("ASoC: wm8960: Add support for the power supplies")
added regulator support to the wm8960 driver, but neglected to update
error handling in the probe function. This results in warning backtraces
if the probe function fails.

Fixes: 422f10adc3eb ("ASoC: wm8960: Add support for the power supplies")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Fabio Estevam <festevam@denx.de>
Link: https://lore.kernel.org/r/20230909120237.2646275-1-linux@roeck-us.net
Signed-off-by: Mark Brown <broonie@kernel.org>