[media] hdmi: added unpack and logging functions for InfoFrames

When receiving video it is very useful to be able to unpack the InfoFrames.
Logging is useful as well, both for transmitters and receivers.

Especially when implementing the VIDIOC_LOG_STATUS ioctl (supported by many
V4L2 drivers) for a receiver it is important to be able to easily log what
the InfoFrame contains. This greatly simplifies debugging.

Signed-off-by: Martin Bugge <marbugge@cisco.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>