PCI: Make PCI_ROM_ADDRESS_MASK a 32-bit constant

PCI: Make PCI_ROM_ADDRESS_MASK a 32-bit constant

commit 76dc52684d0f72971d9f6cc7d5ae198061b715bd upstream.

A 64-bit value is not needed since a PCI ROM address consists in 32 bits.
This fixes a clang warning about "implicit conversion from 'unsigned long'
to 'u32'".

Also remove now unnecessary casts to u32 from __pci_read_base() and
pci_std_update_resource().

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>