sci-electronics/systemc: Import systemc-2.3.4-r1 from Gentoo

SystemC is used with Verilator as an alternative to C++.

The `systemc-2.3.4-r1.ebuild` from Gentoo upstream has been renamed to
`systemc-2.3.4.ebuild`. A `-r1` symbolic link has been created
targetting the actual ebuild.

Ebuild contains such differences:
* adjusted KEYWORDS,
* added `src_test` (tests aren't even started using `default_src_test`).

BUG=chromium:1225099
TEST=FEATURES="test" emerge sci-electronics/systemc

Change-Id: Ic41643d71742641953e7691833549af650a07706
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/3137933
Tested-by: Adam Jelinski <ajelinski@antmicro.com>
Tested-by: Dan Callaghan <dcallagh@chromium.org>
Reviewed-by: Dan Callaghan <dcallagh@chromium.org>
Commit-Queue: Dan Callaghan <dcallagh@chromium.org>
5 files changed