media: atmel: atmel-isc: fix asd memory allocation

The subsystem will free the asd memory on notifier cleanup, if the asd is
added to the notifier.
However the memory is freed using kfree.
Thus, we cannot allocate the asd using devm_*
This can lead to crashes and problems.
To test this issue, just return an error at probe, but cleanup the
notifier beforehand.

Fixes: 10626744 ("[media] atmel-isc: add the Image Sensor Controller code")

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>