linux-imx

docs: driver-api: add remaining converted dirs to it

There are a number of driver-specific descriptions that contain a
mix of userspace and kernelspace documentation. Just like we did
with other similar subsystems, add them at the driver-api
groupset, but don't move the directories.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>