PCI: Change pci_bus_alloc_resource() type_mask to unsigned long

The pci_bus_alloc_resource() "type_mask" parameter is used to compare with
the "flags" member of a struct resource, so it should be the same type,
namely "unsigned long".

No functional change because all current IORESOURCE_* flags fit in 32 bits.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>