ARM: mach-shmobile: sh7372 A4MP support

Add support for the sh7372 A4MP power domain
and hook up the FSI/SPU2 device.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>