ASoC: rsnd: unify rdai naming

struct rsnd_dai is called as "rdai",
but its size has been called as "dai_nr".
Unify these as "rdai"

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

diff --cc sound/soc/sh/rcar/core.c
Simple merge

diff --cc sound/soc/sh/rcar/rsnd.h
Simple merge