[SPARC64]: Fix PCI interrupts on E450 et al.

When the PCI controller OBP node lacks an interrupt-map
and interrupt-map-mask property, we need to form the
INO by hand.  The PCI swizzle logic was not doing that
properly.

This was a regression added by the of_device code.

Signed-off-by: David S. Miller <davem@davemloft.net>