ASoC: fsi-hdmi: remove unneeded header

This patch solve below report from Guennadi.
But I didn't remove #include <sound/sh_fsi.h>.
Because it have FSI_PORT_B define which is used on this file.

> +#include <linux/platform_device.h>
> +#include <sound/sh_fsi.h>
> +#include <video/sh_mobile_hdmi.h>

Now that everything is done with strings - do you still need these
headers?

Reported-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>