fsl-asoc-card: Add support for using the ALC5645 codec

This change enables the rt5645 driver and it's dependencies as well as
configures the fsl-asoc-card driver to include support for the rt5645 codec
driver.

This makes things work.

Test: Audio output works, is routed by default to the speaker.

Change-Id: I36ad016663d9736d05a6b99f8627a00092b219de
3 files changed