This is a follow-up commit to "Increase default warning level", which
overrides Genode's new default warning level for targets contained in
higher-level repositories. By explicitly whitelisting all those targets,
we can selectively adjust them to the new strictness over time - by
looking out for 'CC_CXX_WARN_STRICT' in the target description files.
Issue #465
The main feature for this version upgrade is the use of the instruction
emulator (IEM) to speed up execution and less often the slow recompiler.
issue #2059