drm/bridge: dw-hdmi-qp: fix multi-channel audio output

drm/bridge: dw-hdmi-qp: fix multi-channel audio output

[ Upstream commit cffcb42c57686e9a801dfcf37a3d0c62e51c1c3e ]

Channel Allocation (PB4) and Level Shift Information (PB5) are
configured with values from PB1 and PB2 due to the wrong offset
being used. This results in missing audio channels or incorrect
speaker placement when playing multi-channel audio.

Use the correct offset to fix multi-channel audio output.

Fixes: fd0141d1a8a2 ("drm/bridge: synopsys: Add audio support for dw-hdmi-qp")
Reported-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
Reviewed-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
Link: https://patch.msgid.link/20260228112822.4056354-1-christianshewitt@gmail.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>