drm/bridge: split HDMI Audio from DRM_BRIDGE_OP_HDMI

As pointed out by Laurent, OP bits are supposed to describe operations.
Split DRM_BRIDGE_OP_HDMI_AUDIO from DRM_BRIDGE_OP_HDMI instead of
overloading DRM_BRIDGE_OP_HDMI.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250314-dp-hdmi-audio-v6-1-dbd228fa73d7@oss.qualcomm.com


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>