fixed bunch of bugs that were entered in last commit of hello_world example
These bugs caused it to: 1. always run in finite mode, and 2. avoid priniting
anything about the traffic that passed

Change-Id: I7b5d44eb3803d91ed328e18d61473ed57f43e62e
Signed-off-by: Avner BenHanoch <avnerb@mellanox.com>