Patch from Lennert Buytenhek

- The PCI2050B bridge is not wired to any interrupt pin.
- The SPI-3 option board slot is wired to PCI_B.
- Don't printk every time enp2611_map_pci_irq is called.
- Complain loudly if we encounter an unknown device.

Signed-off-by: Lennert Buytenhek
Signed-off-by: Russell King