drm/vc4: hdmi: Reset audio infoframe on encoder_enable if previously streaming

If the encoder is disabled and re-enabled (eg mode change) all infoframes
are reset, whilst the audio subsystem know nothing about this change.
The driver therefore needs to reinstate the audio infoframe for
itself.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://patchwork.freedesktop.org/patch/msgid/cd579ccc2c9b9d2fce0ebaf32f847cedb0e4a7a2.1599120059.git-series.maxime@cerno.tech