[media] IX2505V Keep I2C gate control alive

Gate could close after first I2C message. On stv0288 it does.
 Keep 2nd and 3rd message I2C gate control alive.
 Remove unnecessary gate closing in this module.

Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>