* mach/Versions (libc: GLIBC_2.0)

* mach/Versions (libc: GLIBC_2.0)

	[SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)]: Conditionalize
	__vm_allocate on this.
	[SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)]: Conditionalize
	mutex- and spinlock-related symbols on this.
	[!SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)] (libc: HURD_CTHREADS_0.3):
	New version set.  Lock-related symbols go here instead in this case.
	* sysdeps/mach/hurd/Versions (libc: GLIBC_2.0): Remove
	_cthread_exit_routine, _cthread_init_routine, cthread_keycreate,
	cthread_getspecific, cthread_setspecific, __libc_getspecific.
	* hurd/Versions
	[SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)] (libc: GLIBC_2.0):
	Put them here instead.
	[!SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_2)] (libc: HURD_CTHREADS_0.3):
	New version set.  Those cthreads symbols go here instead in this case.
	* Versions.def (libc) [USE_IN_LIBIO]: Add HURD_CTHREADS_0.3 version.