ARM: berlin: prepare simple-mfd/syscon conversion of sys/chip ctrl nodes

The chip and system controller nodes will be handled by simple-mfd based
driver probing. Prepare the conversion by adding "simple-mfd" and "syscon"
compatibles to the corresponding nodes.

Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>