ASoC: rsnd: don't call free_irq() on Parent SSI

If SSI uses shared pin, some SSI will be used as parent SSI.
Then, normal SSI's remove and Parent SSI's remove
(these are same SSI) will be called when unbind or remove timing.
In this case, free_irq() will be called twice.
This patch solve this issue.

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