Build infrastructure for GCC 3.4

Build infrastructure for GCC 3.4

This is based both on the logical structure of GCC own Makefiles
and the build framework of GCC 3.3. For the moment, the generated
helper files are recreated for each directory using them to make
the dependencies simpler. libgcc_r is not included, because the
only difference is the normal version is an explicit call to
pthread_mutex_init instead of using the static init model, which
is serialized by a spinlock for all those locks.

This is not yet hooked into the normal buildworld system.