ASoC: tegra-alt: support for button detection

ASoC: tegra-alt: support for button detection

The machine driver has the callback registed, whenever any
jack event happens (button or jack plug/unplug) the notifer
block gets called and the switch state is altered. The jack
events are reported to ASoC by codec driver. Machine driver
handles only the switch state and ignores button events.

Bug 200148270

Change-Id: I456ea5bfb5702483871d795e2f0f7592f7bdec37
Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Reviewed-on: http://git-master/r/929021
GVS: Gerrit_Virtual_Submit
Reviewed-by: Ravindra Lokhande <rlokhande@nvidia.com>