ARM: shmobile: Per-CPU SMP boot / sleep code for SCU SoCs

Hook in the per-CPU boot and sleep code in the shared
mach-shmobile SCU code. CPUs may be kept in the asm
routine until ->boot_secondary() when the per-CPU
boot vector is installed. At the end of ->die() the
asm sleep routine is invoked.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>