ARM: shmobile: koelsch: Add da9063 PMIC device node for system restart

Add a device node for the da9063 PMIC, with subnodes for rtc and wdt.
Regulator support is not yet included.

This allows the system to be restarted when the watchdog timer times
out, or when a system restart is requested.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>