ARM: 7594/1: Add .smp entry for REALVIEW_EB

The REALVIEW EB board can host tiles with multiple cores thus needs
to be able to initialise SMP. There is, however, no .smp entry in
the MACHINE_START struct for REALVIEW_EB.

This patch adds the appropriate .smp entry to this struct.

Signed-off-by: Steve Capper <steve.capper@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>