V4L/DVB (11462): gspca - m5602-po1030: Split up the init into init and start

Split up the po1030 init into start and init. Add a start function.

Signed-off-by: Erik Andr?n <erik.andren@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>