Fixed missing directories in the libraries target: - in the elf case, csu must be built and installed before any shared   libraries.  It wasn't, but we usually used a stale version that   happened to work.  E.g., in the !NOTOOLS case we used the version   built and installed by the bootstrap-libraries target.  Only cross   building was completely broken. - the shared libmd must be built and installed before any shared   libraries that link to it.  It wasn't, but we sometimes used a stale   version that happened to work, as above.  For elf, this caused   bogus linkage of the target shared libatm and libopie with the host   static libmd.  It isn't clear what this actually breaks, except for   cross compiling.  For aout, the shared libmd is not built at all, so   all shared libraries linked to libmd may be broken.  The linker   reports them by spewing RRS warnings.
Fixed missing directories in the libraries target:
- in the elf case, csu must be built and installed before any shared
  libraries.  It wasn't, but we usually used a stale version that
  happened to work.  E.g., in the !NOTOOLS case we used the version
  built and installed by the bootstrap-libraries target.  Only cross
  building was completely broken.
- the shared libmd must be built and installed before any shared
  libraries that link to it.  It wasn't, but we sometimes used a stale
  version that happened to work, as above.  For elf, this caused
  bogus linkage of the target shared libatm and libopie with the host
  static libmd.  It isn't clear what this actually breaks, except for
  cross compiling.  For aout, the shared libmd is not built at all, so
  all shared libraries linked to libmd may be broken.  The linker
  reports them by spewing RRS warnings.

Note that building src/lib early and building subdirs of src/lib in
the correct order in src/lib/Makefile doesn't help, since the subdirs
are all built before any are installed.

Fixed bitrot in the comments about the ordering requirements.

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase