drivers: bus: Add ti-sysc bus driver ...

Adds minimal support for the sysc interconnect target module found
on many TI SoCs. With this device tree includes have been rearagned.
We need the driver to probe the child devices of the bus.

Signed-off-by: Teresa Remmet <t.remmet@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>