media: ti-vpe: cal: Use CAMERARX subdev s_stream op in video device code

Replace calls to cal_camerarx_start() and cal_camerarx_stop() with usage
of the .s_stream() subdev operation. This requires calling the
.set_fmt() operation as the CAMERARX now relies on the format
information set through the subdev API instead of receiving it in the
cal_camerarx_start() function.

This change prepare for exposing the CAMERARX subdev operations to
userspace by using the same API within the kernel.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Benoit Parrot <bparrot@ti.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>