ASoC: wm8400: Use devm_snd_soc_register_component()

Since the remove callback is removed, the snd_soc_unregister_component()
is missing when remove device. Using devm_snd_soc_register_component()
instead of snd_soc_register_component().

Fixes: 10dc44c6 ("ASoC: wm8400: replace codec to component")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>