PCI: Add DMA alias quirk for PLX PEX NTB

PCI: Add DMA alias quirk for PLX PEX NTB

[ Upstream commit 7b90dfc4873b87c468cc6046538f46a531c1d785 ]

The PLX PEX NTB forwards DMA transactions using Requester IDs that don't
exist as PCI devices.  The devfn for a transaction is used as an index into
a lookup table storing the origin of a transaction on the other side of the
bridge.

Alias all possible devfns to the NTB device so that any transaction coming
in is governed by the mappings for the NTB.

Signed-off-by: James Sewart <jamessewart@arista.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>