media: rkisp1: isp: Start CSI-2 receiver before ISP

Make sure the ISP is ready to receive data before starting the CSI-2
receiver by starting it first. Similarly, stop the CSI-2 receiver before
the ISP when stopping streaming.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Dafna Hirschfeld <dafna@fastmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>