ASoC: wm8731: Disable the regulator when probing fails

When the driver fails during probing, the driver should disable the
regulator, not just handle it in wm8731_hw_init().

The following log reveals it:

[   17.812483] WARNING: CPU: 1 PID: 364 at drivers/regulator/core.c:2257 _regulator_put+0x3ec/0x4e0
[   17.815958] RIP: 0010:_regulator_put+0x3ec/0x4e0
[   17.824467] Call Trace:
[   17.824774]  <TASK>
[   17.825040]  regulator_bulk_free+0x82/0xe0
[   17.825514]  devres_release_group+0x319/0x3d0
[   17.825882]  i2c_device_probe+0x766/0x940
[   17.829198]  i2c_register_driver+0xb5/0x130

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Link: https://lore.kernel.org/r/20220405121038.4094051-1-zheyuma97@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>