Signed-off-by: Michael Brown <mcb30@ipxe.org>

Move most arch/i386 files to arch/x86, and adjust the contents of the
Makefiles and the include/bits/*.h headers to reflect the new
locations.

This patch makes no substantive code changes, as can be seen using a
rename-aware diff (e.g. "git show -M5").

This patch does not make the pcbios platform functional for x86_64; it
merely allows it to compile without errors.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Relicence files with kind permission from the following contributors:

  Alex Williamson <alex.williamson@redhat.com>
  Eduardo Habkost <ehabkost@redhat.com>
  Greg Jednaszewski <jednaszewski@gmail.com>
  H. Peter Anvin <hpa@zytor.com>
  Marin Hannache <git@mareo.fr>
  Robin Smidsrød <robin@smidsrod.no>
  Shao Miller <sha0.miller@gmail.com>
  Thomas Horsten <thomas@horsten.com>

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Marin Hannache <git@mareo.fr>
Signed-off-by: Michael Brown <mcb30@ipxe.org>