machine maintainer ping: microblaze

[Roland McGrath]

Please review and approve (or commit) the roland/nptl-microblaze branch ASAP.
(Two patches so far, previously posted a while ago.  May be more posted soon.)

Then please follow on ASAP (this week would be nice!) with the vfork
consolidation, or else tell me ASAP what I need to know to try it myself:
* Can you rely on IFUNC?
* If not, can you rely on the C compiler to emit a proper tail call, that
  cannot touch the stack, for a trivial argumentless tail call in C?
* If not, what does the assembly (.S) look like for a tail call to a PLT
  function?  e.g. on x86 it's "jmp JUMPTARGET(foobar)".


Thanks,
Roland