sim: Add faulting flag to instruction tracing interface

sim: Add faulting flag to instruction tracing interface

This patch adds a faulting flag to InstRecord.
This allows tracers to identify that the traced instruction has
faulted, when ExecFaulting is enabled. It can be set with
InstRecord::setFaulting() and read with Instrecord::getFaulting().

Change-Id: I390392d59de930533eab101e96dc4d3c76500748
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/30134
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>