[media] xc4000: make checkpatch.pl happy

Solve the ./scripts/checkpatch.pl compliants for the patches
that added xc4000 support, including a few changes at dib0700.

While here, remove a few printk noise by converting some msgs
into debug ones.

Cc: Istvan Varga <istvan_v@mailbox.hu>
Cc: Patrick Boettcher <pboettcher@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>