PCI: cadence: Fix to read 32-bit Vendor ID/Device ID property from DT

PCI: cadence: Fix to read 32-bit Vendor ID/Device ID property from DT

The PCI Bus Binding specification (IEEE Std 1275-1994 Revision 2.1 [1])
defines both Vendor ID and Device ID to be 32-bits. Fix
pcie-cadence-host.c driver to read 32-bit Vendor ID and Device ID
properties from device tree.

[1] -> https://www.devicetree.org/open-firmware/bindings/pci/pci2_1.pdf

Link: https://lore.kernel.org/r/20200508130646.23939-4-kishon@ti.com
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Tom Joseph <tjoseph@cadence.com>