ASoC: fsl: remove unnecessary dai_link->platform

dai_link->platform is no longer needed if CPU and Platform are
same Component. This patch removes unnecessary dai_link->platform.
Dummy Platform is also not necessary.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87o7ojjd06.wl-kuninori.morimoto.gx@renesas.com


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