iommu/dma: Reserve IOVA for PCIe inaccessible DMA address

The dma_ranges list field of PCI host bridge structure has resource entries
in sorted order representing address ranges allowed for DMA transfers.

Process the list and reserve IOVA addresses that are not present in its
resource entries (ie DMA memory holes) to prevent allocating IOVA addresses
that cannot be accessed by PCI devices.

Based-on-a-patch-by: Oza Pawandeep <oza.oza@broadcom.com>
Signed-off-by: Srinath Mannam <srinath.mannam@broadcom.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Oza Pawandeep <poza@codeaurora.org>
Acked-by: Robin Murphy <robin.murphy@arm.com>