ARM: dts: Configure interconnect target module for am437x rfbi

ARM: dts: Configure interconnect target module for am437x rfbi

We can now probe devices with device tree only configuration using
ti-sysc interconnect target module driver. Let's configure the
module and drop "ti,hwmods" peroperty as this module is a child node
of dispc and has no dependencies to to legacy platform data.

Cc: Jyri Sarha <jsarha@ti.com>
Cc: Keerthy <j-keerthy@ti.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>