Re-implement GUEST_BASE support.
Offset guest ddress space by default if the guest binary contains
regions below the host mmap_min_addr.
Implement support for i386, x86-64 and arm hosts.
Signed-off-by: NRiku Voipio <riku.voipio@iki.fi>
Signed-off-by: NPaul Brook <paul@codesourcery.com>