hv_netvsc: ignore devices that are not PCI

[ Upstream commit b93c1b5ac8643cc08bb74fa8ae21d6c63dfcb23d ]

Registering another device with same MAC address (such as TAP, VPN or
DPDK KNI) will confuse the VF autobinding logic.  Restrict the search
to only run if the device is known to be a PCI attached VF.

Fixes: e8ff40d4 ("hv_netvsc: improve VF device matching")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>