ARM: SoC: convert shmobile SMP to SMP operations

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

Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Magnus Damm <magnus.damm@gmail.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>