ASoC: add mclk-fs to audio graph card binding

Add mclk-fs support to audio graph card
as initially supported in simple card.
Signed-off-by: Olivier Moysan <olivier.moysan@st.com>
Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

Documentation/devicetree/bindings/sound/audio-graph-card.txt

@@ -17,6 +17,7 @@ Below are same as Simple-Card.
 - bitclock-master
 - bitclock-inversion
 - frame-inversion
+- mclk-fs
 - dai-tdm-slot-num
 - dai-tdm-slot-width
 - clocks / system-clock-frequency