pcap.core: making some classes final

pcap.core: making some classes final

This patch is to make some classes final in pcap.core component.
It should be final to improve readability and since you should never extend
it. It also allows the jvm to inline methods and improve performance.

Change-Id: I7288b25324cb343a33cf6536b80cdaae3619211f
Signed-off-by: Wassim <wassim.nasrallah.36@gmail.com>
Reviewed-on: https://git.eclipse.org/r/73671
Reviewed-by: Hudson CI
Reviewed-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Tested-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Reviewed-by: Genevieve Bastien <gbastien+lttng@versatic.net>
Tested-by: Genevieve Bastien <gbastien+lttng@versatic.net>