[media] imon: Use large delays earlier

send_packet() is used during initialization, before send_packet_delay
is set. So, move ictx->send_packet_delay to happen earlier.

[mchehab@redhat.com: fold two patches into one to make git history clearer]
Signed-off-by: Kevin Baradon <kevin.baradon@gmail.com>

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>