bus: ti-sysc: Add support for platform data callbacks

We want to pass the device tree configuration for interconnect target
modules from ti-sysc driver to the existing platform hwmod code.

This allows us to first validate the dts data against the existing
platform data before we start dropping the platform data in favor of
device tree data.

To do this, let's add platform data callbacks for PM runtime functions
to call for the interconnect target modules if platform data is
available.

Note that as ti-sysc driver can rebind, omap_auxdata_lookup and related
functions can no longer be __init.

Signed-off-by: Tony Lindgren <tony@atomide.com>