media: controls: Log H264 stateless controls in .std_log

For now, only print the type of the control. In the future,
we might want to be able to print the values of all
the stateless codec controls currently set in the control handler,
which should be useful for debugging reasons.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>