Add pcb1 to the QCA955x.

The Tp-link Archer-C7v2 unit has a QCA9558 internally but hangs the
QCA988x 11ac PCIe NIC off of PCI RC #1, not #0.

So I actually finally /do/ have a board to verify whether PCIe is working.
Grr.

Tested:

• TP-Link Archer-C7v2.