ASoC: rsnd: fixup forever loop bug on SSI

commit b5b442ab ("ASoC: rsnd: add .irq callback")
added .irq support, and it cares both parent SSI and normal SSI.
But it should care only normal SSI. Otherwise SSI might be
forever loop if SSI is used as both parent SSI and normal SSI
(= 2 users), and if under/over run error happen. Because irq disable
do nothing in such case. This patch solve this issue.

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