iommu/omap: Add registration for DT fwnode pointer

The fwnode pointer must be passed to the iommu core, so that the core
can map the IOMMU towards device requests properly. Without this, some
IOMMU clients like OMAP remoteproc will fail the iommu configuration
multiple times with -EPROBE_DEFER, which will eventually be ignored with
a kernel warning banner.

Signed-off-by: Tero Kristo <t-kristo@ti.com>
Link: https://lore.kernel.org/r/20200424145828.3159-1-t-kristo@ti.com


Signed-off-by: Joerg Roedel <jroedel@suse.de>