ASoC: mx27vis: retrieve gpio numbers from platform_data

Rather than including mach/iomux-mx27.h to define gpio numbers and set
up the pins, the patch moves all these into machine code and has the
gpio numbers passed to driver via platform_data.  As the result, we
can remove the mach/iomux-mx27.h inclusion from driver.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Javier Martin <javier.martin@vista-silicon.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>