Revert "audio: hdmi: add dynamic multichannel support"

Not necessary. Removed HDMI support.

This reverts commit b12d9b4d5a621685f55cdba96b5aa49352e4a5db.
Revert "omap4-common: force landscape when hdmi is connected"

Not necessary, HDMI support removed.

This reverts commit af800ca094d9395c36a5a625dc3b0028b4433a70.
Revert "audio: Add a separate HAL for HDMI audio"
Not necessary, HDMI removed.
This reverts commit 056878771a660406f39fd841141fa93f9df6b0a8.