pci: definition of pci_addr_t and pci_size_t

Currently the size of pci_addr_t and pci_size_t depends on
CONFIG_SYS_PCI_64BIT. For qemu_arm64_defconfig with 4 GiB RAM this leads
to an error

    pci_hose_phys_to_bus: invalid physical address

which is due to the truncation of the bus address in _dm_pci_phys_to_bus.

Defining CONFIG_SYS_PCI_64BIT is not a solution as this results in an error

   PCI: Failed autoconfig bar 10

So let's use unsigned long for pci_addr_t and pci_size_t if
CONFIG_SYS_PCI_64BIT is not defined.

Considering that 32bit U-Boot is used to launch some 64bit x86 systems we
cannot do without CONFIG_SYS_PCI_64BIT requiring u64 as type.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>