systemc: Update the testing framework to get it working again.

The systemc testing framework is not used regularly, and had bit rot and
stopped working. This change updates it so that it runs again, and all
previously passing tests pass again.

These changes were mostly in the related SConscript now that top level
targets are built a little differently and that the gem5 shared library
is no longer stored in a special construction environment variable.
verify.py also needed to be updated since warn() and info() lines now
have file and line number information in them, throwing off pre diff
filtering of gem5 outputs.

Change-Id: Ifdcbd92eab8b9b2168c449bfbcebf52dbe1f016a
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/54324
Maintainer: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
2 files changed