drm/bridge: lt9611: rework infoframes handling

Rework handling infoframes:
- Write full HDMI AVI infoframe instead of just fixing the VIC value
- Also send the HDMI Vendor Specific infoframe, as recommended by the
  HDMI spec.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>