ASoC: DaVinci: Update suspend/resume support for McASP driver

Add clock enable and disable calls to resume and suspend respectively.
Also add a member to the audio device data structure which tracks the clock
status.

Tested on DA850/OMAP-L138 EVM. For the purpose of testing, the patches[1] which
add suspend-to-RAM support to DA850/OMAP-L138 SoC were applied.

[1] http://linux.davincidsp.com/pipermail/davinci-linux-open-source/
2009-November/016958.html

Signed-off-by: Chaithrika U S <chaithrika@ti.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/davinci/davinci-mcasp.h b/sound/soc/davinci/davinci-mcasp.h
index 582c924..e755b51 100644
--- a/sound/soc/davinci/davinci-mcasp.h
+++ b/sound/soc/davinci/davinci-mcasp.h
@@ -44,6 +44,7 @@
 	int sample_rate;
 	struct clk *clk;
 	unsigned int codec_fmt;
+	u8 clk_active;
 
 	/* McASP specific data */
 	int	tdm_slots;