ASoC: core: Implement devm_snd_soc_register_component()

Since with the wider use of devres many drivers are now only calling
snd_soc_unregister_component() in their remove functions providing a
managed version will save a reasonable amount of code.

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

diff --cc include/sound/soc.h
Simple merge

diff --cc sound/soc/Makefile
Simple merge

diff --cc sound/soc/soc-devres.c
Simple merge