ARM: 8496/1: OMAP: RX51: save ATAGS data in the early boot stage

This fixes a regression with device tree based booting compared to legacy booting for n900 to make the n900 legacy user space to also work with device tree based booting

Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>