drm/amd/display: set Layout properly for 8ch audio at timing validation

Why:
For audio packet type 0x02, there are 2 Layouts:
   Layout = 0 for 2 channels
and Layout = 1 for > 2 channels.
Layout will affect bandwidth check.

Currently, for HDMI FRL, Layout field isn't set and has a default value
of 0, so theoretically only 2-channel audio for audio packet type 0x02
is supported now.

How:
1. Set Layout properly according to maximum audio channel numbers for
audios with audio packet type 0x02.
2. 8ch LPCM audio is not supported for timing modes with v_active <= 576.
Reviewed-by: Chris Park <chris.park@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Acked-by: Agustin Gutierrez <agustin.gutierrez@amd.com>
Signed-off-by: Bing Guo <Bing.Guo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce/dce_audio.c

@@ -514,13 +514,15 @@ void dce_aud_az_configure(
 			union audio_sample_rates sample_rates =
 					audio_mode->sample_rates;
 			uint8_t byte2 = audio_mode->max_bit_rate;
+			uint8_t channel_count = audio_mode->channel_count;
 
 			/* adjust specific properties */
 			switch (audio_format_code) {
 			case AUDIO_FORMAT_CODE_LINEARPCM: {
+
 				check_audio_bandwidth(
 					crtc_info,
-					audio_mode->channel_count,
+					channel_count,
 					signal,
 					&sample_rates);
 
@@ -548,7 +550,7 @@ void dce_aud_az_configure(
 
 			/* fill audio format data */
 			set_reg_field_value(value,
-					audio_mode->channel_count - 1,
+					channel_count - 1,
 					AZALIA_F0_CODEC_PIN_CONTROL_AUDIO_DESCRIPTOR0,
 					MAX_CHANNELS);