* sysdeps/unix/sysv/linux/Makefile
($(objpfx)syscall-%.h $(objpfx)syscall-%.d): Take code from
sparc/Makefile to produce a bi-arch file as needed.
That's now parameterized by the variable $(64bit-predefine).
Use LC_ALL=C for `comm' commands in that rule.
No longer conditional on [$(no_syscall_list_h)].
* sysdeps/unix/sysv/linux/sparc/Makefile: Remove replacement rules.
(64bit-predefine): New variable.
* sysdeps/unix/sysv/linux/x86_64/Makefile: Likewise.
* sysdeps/unix/sysv/linux/s390/Makefile: New file.
* sysdeps/unix/sysv/linux/powerpc/Makefile
(64bit-predefine): New variable.
* login/utmp-private.h: Declare __libc_utmp_lock.
* sysdeps/unix/getlogin_r.c (getlogin_r): Take __libc_utmp_lock once
call __libc_utmp_jump_table functions directly, instead of using
__setutent et al.
* sysdeps/unix/sysv/linux/configure.in: Use case instead of if.
* sysdeps/unix/sysv/linux/configure: Regenerated.