Clean up and refactor i386 sub-architecture setup.

This change moves all the code from the
asm-i386/mach-*/setup_arch_pre/post.h headers, into
arch/i386/mach-*/setup.c.  mach-*/setup_arch_pre.h is renamed to
setup_arch.h, and contains only things which should be in header files.  It
is purely code-motion; there should be no functional changes at all.

Several functions in arch/i386/kernel/setup.c needed to be made non-static
so that they're visible to the code in mach-*/setup.c.  asm-i386/setup.h is
used to hold the prototypes for these functions.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Cc: Martin Bligh <mbligh@google.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Andrey Panin <pazke@donpac.ru>
Cc: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>