ASoC: simple-scu-card: tidyup "Sampling Rate Conversion"

"Sampling Rate Conversion" is better than "Sampling Rate Convert"

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