media: v4l: vsp1: Move vsp1_video_pipeline_setup_partitions() function

Separate the code change from the function move so that code changes can
be clearly identified. This commit has no functional change.

The partition algorithm functions will be changed, and
vsp1_video_pipeline_setup_partitions() will call vsp1_video_partition().
To prepare for that, move the function without any code change.

Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>