ARM: omap2+: control: add support for auxiliary control module instances

Control module can have multiple instances in a system, each with separate
address space and features. Add base support for these auxiliary instances,
with support for syscon and clock mappings under them.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>