ASoC: fsl_ssi: Use devm_snd_soc_register_component()

Using devm_snd_soc_register_component() can make the code shorter and
cleaner.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>