Rename LwIP library in preparation for removal of LwIP libc plugin. The
current LwIP library will be replaced with a new version stripped of its
synchronous socket support. The next version will be incompatible with
the current, so removing 'lwip.lib.so' completely for a period makes it
easy to identify legacy users.
Fix#2797
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
Currently, LxIP peers need a lot of RAM (the simple test-client/server for the
nic_router test need at least 28 MB per component). As the nic_router test
previously used 6 instances of such components and a lot of other components,
it had issues with insufficient RAM on some platforms. By using two new
LwIP-based UDP tests instead, we save more than 100 MB.
Ref #2543
