[PATCH] Add a.out support for x86-64

[PATCH] Add a.out support for x86-64

From: Andi Kleen <ak@muc.de>

Add 32bit a.out support for x86-64.

Not exactly an important bug fix, but maybe it will help someone.  This
should increase the current 98% compatibility to i386 to perhaps 98.1% @)

I tested an old a.out SuSE 4.2 installation in chroot and it worked.  It
also ran some very old linux binaries from '92 found on ftp.funet.fi.  The
only program that didn't was the SuSE a.out GNU emacs, but I was too lazy
to track that down.  Core dumps are not supported.