This patch adds controls to set following ALC parameters,
 - Max gain, Min gain, Noise gain, Attack rate, Release rate and delay

It also adds a switch to enable/disable noise suppression.

As per DA7210 data sheet, ALC and noise suppression can be enabled
only if certain conditions are met. This condition checks are handled
by simply using "_EXT" version of controls to capture change events.
Signed-off-by: Ashish Chavan <ashish.chavan@kpitcummins.com>
Signed-off-by: David Dajun Chen <dchen@diasemi.com>
Acked-by: Liam Girdwod <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>