ASoC: rsnd: TDM 6ch needs 8ch clock for hw refine

Renesas sound needs 8ch clock if TDM 6ch mode, and needs 2ch clock for
6ch or 8ch sound if Multi SSI mode. And these are related to before/after
CTU (= Channel Transfer Unit).
To calculate these we already has rsnd_runtime_channel_for_ssi() which
returns runtime necessary channels.
But, it based on runtime->channels  which is not yet set when hw refine.
We need to use hw_params instead of runtime->xxx when hw refine,
and it is not needed after runtime was set.
This patch adds new hw_params on rsnd_dai_stream, and it will be removed
on rsnd_hw_params().
This is very temporary durty code, but it seems no choice at this point.

Tested-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>