ASoC: rsnd: always call probe/remove for MUX

CTU/MUX/DVC/SSIU/SSI/Audio-DMAC-periperi might be used under multipath.
So, probe()/remove() need to be called multiple times.
This patch allows it.

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