hal: Refactor HDMI backend configuration

-In current design HDMI backend configuration does not validate
incoming configuration against what is supported by the
connected sink ( using edid). This results in an incorrect
configuration of the HDMI backend, sometimes leading to no audio.
-Move HDMI backend configuration to
platform_check_and_set_codec_backend_cfg, this design ensures
that HDMI backend configuration happens with valid and only
supported parameters (sample rate, channels and bit width)
by the connected sink.
-Remove usleep from keep_alive and move to conditional timed wait,
this ensures to break from the keep_alive loop quickly, instead
of waiting for the complete usleep duration.

CRs-Fixed: 1039831
Change-Id: Id46ae76575f1b8169370cee817b505b97af8fe01