ASoC: sh: fsi: enable chip specific data transfer mode

SupherH FSI2 can use special data transfer,
but it depends on CPU-FSI2 connection style.

We can use 16bit data stream mode if it was valid connection,
and it is required for 16bit data DMA transfer / SPDIF sound output.
We can use 24bit data transfer if it was invalid connection.

We can select connection type if CPU is SH7372,
and it is always valid connection if latest SuperH.

This patch adds new bus_option and fsi_bus_setup()
for supporting these feature.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>