ASoC: s6000: Don't mix SNDRV_PCM_RATE_CONTINUOUS with specific rates

SNDRV_PCM_RATE_CONTINUOUS means that all rates (possibly limited to a certain
interval) are supported. There is no need to manually set other rate bits.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Daniel Glöckner <daniel-gl@gmx.net>
Signed-off-by: Mark Brown <broonie@linaro.org>