ASoC: soc-dai: cleanup cppcheck warning at snd_soc_pcm_dai_new()

This patch cleanups below cppcheck warning.

sound/soc/soc-dai.c:553:13: style: Variable 'ret' is assigned a value that is never used. [unreadVariable]
 int i, ret = 0;
            ^

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87wnomyom1.wl-kuninori.morimoto.gx@renesas.com


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