ASoC: soc-dai.h: add missing snd_soc_dai_set_widget()

Current ASoC has snd_soc_dai_get_widget() (= _get_) but doesn't
have _set_ function. This patch adds it.

This patch also cleanup unnecessary line break for  _get_ function.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/87bkmfforp.wl-kuninori.morimoto.gx@renesas.com


Signed-off-by: Mark Brown <broonie@kernel.org>