PCI: rcar: Remove rcar_pcie_setup_window() resource argument

rcar_pcie_setup_window() took both the window number and the resource,
which was redundant because we can look up the resource from the window
number.

Remove the "res" argument.

Signed-off-by: Phil Edworthy <phil.edworthy@renesas.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>