ASoC: fsi codecs: modify menu attribute on Kconfig

Current SND_FSI_xxx menu attributes were bool,
but it should be tristate.
This patch solve below report from Guennadi

"bool" means, if someone is linking the whole ASoC into the kernel, they
will not be able to build this as a module. Not a big deal, but you're
stealing some freedom from the user.

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