fastmodel,dev: Replace the reset port with a Signal*Port<bool>.

The ResetRequestPort and ResetResponsePort have a few problems:

1. A reset signal should happen during the time a reset is asserted,
or in other words the device should stay in reset and not doing
anything while reset is asserted. It should not immediately restart
execution while the reset is still held.

2. These names are misleading, since there is no response. These names
are inherited from other port types where there is an actual response.

There is a new generic SignalSourcePort and SignalSinkPort set of port
classes which are templated on the type of signal they propogate, and
which can be used in place of reset ports in c++. These ports can
still have a specialized role which will ensure that only reset ports
are connected to each other for a form of type checking, although
the underlying c++ instances are more interoperable than that.

Change-Id: Id98bef901ab61ac5b200dbbe49439bb2d2e6c57f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/66675
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Yu-hsin Wang <yuhsingw@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/dev/SConscript

@@ -36,9 +36,7 @@ Source('dma_device.cc')
 Source('dma_virt_device.cc')
 
 SimObject('IntPin.py', sim_objects=[])
-
 SimObject('ResetPort.py', sim_objects=[])
-Source('reset_port.cc')
 
 DebugFlag('IsaFake')
 DebugFlag('DMA')