Move architecture cases out of sysdeps/unix/sysv/linux/configure.ac.

Move architecture cases out of sysdeps/unix/sysv/linux/configure.ac.

Continuing the process of making non-ex-ports architectures follow the
preferred sysdeps practices followed by ex-ports architectures - that
is, putting things in architecture-specific sysdeps files rather than
having architecture-specific cases in architecture-independent files -
this patch moves architecture cases out of
sysdeps/unix/sysv/linux/configure.ac into (new or existing) configure
fragments for each architecture.  (In the case of the
arch_minimum_kernel setting for x32,
sysdeps/unix/sysv/linux/x86_64/x32/configure already has such a
setting so the setting in sysdeps/unix/sysv/linux/configure.ac was a
duplicate that could just be removed - though I haven't tested for
x32.)

Tested for x86_64 and x86 that the patch causes no changes to the
installed shared libraries or ldd (or any part of the installation
except for the parts that always change because the files contain
timestamps - nscd and static libraries).

	* sysdeps/unix/sysv/linux/configure.ac: Remove cases for
	individual architectures.
	* sysdeps/unix/sysv/linux/configure: Regenerated.
	* sysdeps/unix/sysv/linux/i386/configure.ac: New file.
	* sysdeps/unix/sysv/linux/i386/configure: New generated file.
	* sysdeps/unix/sysv/linux/powerpc/configure.ac
	(ldd_rewrite_script): Define variable.
	* sysdeps/unix/sysv/linux/powerpc/configure: Regenerated.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/configure.ac: New
	file.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/configure: New
	generated file.
	* sysdeps/unix/sysv/linux/s390/configure.ac: New file.
	* sysdeps/unix/sysv/linux/s390/configure: New generated file.
	* sysdeps/unix/sysv/linux/sh/configure.ac: New file.
	* sysdeps/unix/sysv/linux/sh/configure: New generated file.
	* sysdeps/unix/sysv/linux/sparc/configure.ac: New file.
	* sysdeps/unix/sysv/linux/sparc/configure: New generated file.
	* sysdeps/unix/sysv/linux/x86_64/configure.ac: New file.
	* sysdeps/unix/sysv/linux/x86_64/configure: New generated file.