there exists a 'cc', leading to buildlink creating a 'cc' wrapper pointing
to the original 'cc', which then won't work with the gcc flags, while the
'gcc' wrapper does work (since packages simply call 'cc' (or 'gcc') and
rely on buildlink having prepended the path to the right wrapper).
-USE_NEW_TEXINFO, saves some patches
-symlink libiberty.a into build tree instead of buildlink/lib,
saves some patches
-put common make rules into Makefile.common (for all) and
buildaddon.mk (for all but the base "c" pkg)
