[media] s5p-csis: Enable only data lanes that are actively used

Enable only MIPI CSI-2 data lanes at the DPHY that are actively
used, rather than unmasking all unconditionally.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>