Updating top-level autoconf to 2.59

[Steve Ellcey]

> 2006-12-09  Daniel Jacobowitz  <dan@codesourcery.com>
>
>         * Makefile.tpl (build_alias, host_alias, target_alias): Use
>         noncanonical equivalents.
>         * configure.in: Update AC_PREREQ.  Prevent error for AS_FOR_TARGET.
>         Set build_noncanonical, host_noncanonical, and target_noncanonical.
>         Use them.  Rewrite removal of configure arguments for autoconf
>         2.59.  Discard variable settings.
>         * Makefile.in: Regenerated.
>         * configure: Regenerated with autoconf 2.59.

I have done some more testing with this patch and found a problem.  When
I configure with host=/build=/target= set to the platform that I am on I
don't get the gcc and g++ executables in the bin directory, just
<target>-gcc and <target>-g++.  The same holds true for the binutils
commands like ar and as.  So when I did a configure with
'--host=ia64-hp-hpux11.23 --target=ia64-hp-hpux11.23
--build=ia64-hp-hpux11.23' on an HP-UX 11.23 system my bin directory
contained:

ia64-hp-hpux11.23-g++
ia64-hp-hpux11.23-gcc
ia64-hp-hpux11.23-nm
ia64-hp-hpux11.23-size
(etc)

but no g++, gcc, nm, or size commands without the prefix.

Steve Ellcey
sje@cup.hp.com