Convert ux500 platforms to use struct smp_operations to provide
their SMP and CPU hotplug operations.

Cc: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Acked-by: Nsrinidhi kasagar <srinidhi.kasagar@stericsson.com>
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>