* sysdeps/mach/hurd/munlock.c: New file.
* sysdeps/mach/hurd/bits/posix_opt.h (_POSIX_MEMLOCK_RANGE): Define it.
* misc/Makefile (routines): Add mlock munlock mlockall munlockall.
* sysdeps/generic/mlock.c: New file.
* sysdeps/generic/munlock.c: New file.
* sysdeps/generic/mlockall.c: New file.
* sysdeps/generic/munlockall.c: New file.
* sysdeps/generic/bits/mman.h (MCL_CURRENT, MCL_FUTURE): New macros.
* sysdeps/unix/sysv/linux/syscalls.list (mlock, munlock,
mlockall, munlockall): Change caller field to - from EXTRA.
Don't use __ names; not used (and not declared in include/sys/mman.h).
