fbdev: allow passing more than one aperture for handoff

It removes a hack from nouveau code which had to detect which
region to pass to kick vesafb/efifb.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Peter Jones <pjones@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>