[media] s5p-mfc: Add device tree support

This patch will add the device tree support for MFC driver.

Signed-off-by: Arun Kumar K <arun.kk@samsung.com>
Acked-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>