ASoC: simple card: set cpu-dai sysclk with mclk-fs

Allows to request a specific mclk frequency per cpu_dai.
To support some codecs with mclk provided by the cpu_dai, the
mclk rate must be set depending on frame rate.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Signed-off-by: Mark Brown <broonie@kernel.org>