The traffic generator currently assumes that it is always driven from a configuration file. Split it into a base class (BaseTrafficGen) that handles basic packet generation and a derived class that implements the config handling (TrafficGen). Change-Id: I9407f04c40ad7e40a263c8d1ef29d37ff8e6f1b4 Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com> Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com> Reviewed-on: https://gem5-review.googlesource.com/11515