Unify more sys/procfs.h headers.

Unify more sys/procfs.h headers.

This patch continues the process of unifying sys/procfs.h headers for
architectures using the Linux kernel.

A bits/procfs-id.h header is added to define __pr_uid_t and __pr_gid_t
for the types of pr_uid and pr_gid; the default version of this header
uses unsigned int.  On some architectures, sys/procfs.h has copies of
32-bit structures for 64-bit builds; those move into a
bits/procfs-extra.h header (they can't go in bits/procfs.h because
they have to come *after* other declarations from sys/procfs.h).
Given appropriate versions of these headers, six more architectures
can then move to providing only bits/procfs*.h without duplicating the
rest of the contents of sys/procfs.h.  Only alpha needs a further
bits/ header to be added before it can stop having its own
sys/procfs.h.

Tested for x86_64 and x86, and with build-many-glibcs.py.

	* sysdeps/unix/sysv/linux/sys/procfs.h: Include
	<bits/procfs-id.h> and <bits/procfs-extra.h>.
	(struct elf_prpsinfo): Use __pr_uid_t and __pr_gid_t as types of
	pr_uid and pr_gid.
	* sysdeps/unix/sysv/linux/Makefile [$(subdir) = misc]
	(sysdep_headers): Add bits/procfs-id.h and bits/procfs-extra.h.
	* sysdeps/unix/sysv/linux/bits/procfs-extra.h: New file.
	* sysdeps/unix/sysv/linux/bits/procfs-id.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/bits/procfs-id.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/bits/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/m68k/bits/procfs-id.h: Likewise.
	* sysdeps/unix/sysv/linux/m68k/bits/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/bits/procfs-extra.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/bits/procfs-id.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/bits/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/sh/bits/procfs-id.h: Likewise.
	* sysdeps/unix/sysv/linux/sh/bits/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/bits/procfs-extra.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/bits/procfs-id.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/bits/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/bits/procfs-id.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/bits/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/arm/sys/procfs.h: Remove file.
	* sysdeps/unix/sysv/linux/m68k/sys/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/s390/sys/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/sh/sys/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sys/procfs.h: Likewise.
	* sysdeps/unix/sysv/linux/x86/sys/procfs.h: Likewise.