qemu/common : change DEVICE2 definition for MMU

DEVICE2 is not currently used on qemu platform but is needed for
a future patch for qemu_sbsa platform. Change its definition to
RW and add it to all levels of arm-tf similar to DEVICE1 definition.

Signed-off-by: Graeme Gregory <graeme@nuviainc.com>
Change-Id: I03495471bfd423b61ad44ec4953fb25f76aa54bf
1 file changed