audio: fix output flag test in open_output_stream

If flag AUDIO_OUTPUT_FLAG_DIRECT is set, we should only
try to open a multi channel HDMI PCM output if flag
AUDIO_OUTPUT_FLAG_COMPRESS_OFFLOAD is not set.

Bug: 8174410.
Change-Id: I63fe6cabca590e70c077dea13c86c6948700e606

Conflicts:

	hal/audio_hw.c