ASoC: rsnd: merge rsnd_kctrl_new_m/s/e into rsnd_kctrl_new()

Current rsnd driver is using rsnd_kctrl_new_m/s/e function,
but the differences are very few.
This patch merge these rsnd_kctrl_new_m/s/e into rsnd_kctrl_new

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