si4708: configure de-emphasis according to selected band

Change-Id: I881eedb93e6a3def0780e3c9e7726fc90370ec56
FM radio support (part 2)

Modify board config and libaudio to make legacy FM radio switching and
volume control work - this uses some of the QCOM_FM interfaces.

Change-Id: I40d44d4184ba2c89417ff1a8cadd9fbfc9956c5a
Update patch series for FM radio support

* Add legacy FM radio support code into framework
* Modify FmRadioReceiver demo application for legacy FM audio

Change-Id: I0792a189dd4448fb0ae812897a4594d8258c0b19