mem: Minimize the use of MemObject.

MemObject doesn't provide anything beyond its base ClockedObject any
more, so this change removes it from most inheritance hierarchies.
Occasionally MemObject is replaced with SimObject when I was fairly
confident that the extra functionality of ClockedObject wasn't needed.

Change-Id: Ic014ab61e56402e62548e8c831eb16e26523fdce
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18289
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Gabe Black <gabeblack@google.com>

misc: missing override specifier

Missing specifier of overridden virtual function
declared in sim_object.hh

Removed redundant "virtual" keyword

Change-Id: I42aa3349b537c9e62607bce20cf1b3aabdb99bf2
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17468
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

arch, cpu, dev, gpu, mem, sim, python: start using getPort.

Replace the getMasterPort, getSlavePort, and getEthPort functions
with getPort, and remove extraneous mechanisms that are no longer
necessary.

Change-Id: Iab7e3c02d2f3a0cf33e7e824e18c28646b5bc318
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17040
Reviewed-by: Daniel Carvalho <odanrc@yahoo.com.br>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

testers: Refactor some Event subclasses to lambdas

Change-Id: I897b6162a827216b7bad74d955c0e50e06a5a3ec
Signed-off-by: Sean Wilson <spwilson2@wisc.edu>
Reviewed-on: https://gem5-review.googlesource.com/3926
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

ruby: rename networktest to garnet_synthetic_traffic.
networktest is essentially a collection of synthetic traffic patterns
for the network. The protocol name and the tester having the same name
led to multiple python configuration files with the same name, adding
confusion. This patch renames networktest to garnet_synthetic_traffic,
and also adds more synthetic traffic patterns.