drm/bridge: anx7625: Support HDMI_I2S audio format

1. Support HDMI_I2S audio format.
2. Return 0 if there is no sink connection in .hw_param callback.

Signed-off-by: Xin Ji <xji@analogixsemi.com>
Acked-by: Hsin-Yi Wang <hsinyi@chromium.org>
Acked-by: Jiaxin <Yu&lt;jiaxin.yu@mediatek.com>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220726033058.403715-1-xji@analogixsemi.com