PCI/ACPI: Add Ampere Altra SOC MCFG quirk

PCI/ACPI: Add Ampere Altra SOC MCFG quirk

commit 877c1a5f79c6984bbe3f2924234c08e2f4f1acd5 upstream.

Ampere Altra SOC supports only 32-bit ECAM reads.  Add an MCFG quirk for
the platform.

Link: https://lore.kernel.org/r/1596751055-12316-1-git-send-email-tuanphan@os.amperecomputing.com
Signed-off-by: Tuan Phan <tuanphan@os.amperecomputing.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
[ dannf: backport drops const qualifier from pci_32b_read_ops for
  consistency with the other quirks that weren't yet constified in v5.4 ]
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>