Convert the Xilinx host bridge to use the common
pci_parse_request_of_pci_ranges().

There's no need to assign the resources to a temporary list first. Just
use bridge->windows directly and remove all the temporary list handling.
Signed-off-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Andrew Murray <andrew.murray@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Michal Simek <michal.simek@xilinx.com>