We've run into a problem where our device is attached
to a Virtual Machine and the use of the new pci_set_vpd_size()
API doesn't help.  The VM kernel has been informed that
the accesses are okay, but all of the actual VPD Capability
Accesses are trapped down into the KVM Hypervisor where it
goes ahead and imposes the silent denials.

The right idea is to follow the kernel.org
commit 1c7de2b4 ("PCI: Enable access to non-standard VPD for
Chelsio devices (cxgb3)") which Alexey Kardashevskiy authored
to establish a PCI Quirk for our T3-based adapters. This commit
extends that PCI Quirk to cover Chelsio T4 devices and later.

The advantage of this approach is that the VPD Size gets set early
in the Base OS/Hypervisor Boot and doesn't require that the cxgb4
driver even be available in the Base OS/Hypervisor.  Thus PF4 can
be exported to a Virtual Machine and everything should work.

Fixes: 67e65879 ("cxgb4: Set VPD size so we can read both VPD structures")
Cc: <stable@vger.kernel.org>  # v4.9+
Signed-off-by: Casey Leedom <leedom@chelsio.com>
Signed-off-by: Arjun Vynipadath <arjun@chelsio.com>
Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>