For compatibility with bcma(4), map Sonics/OCP per-core address
spaces to bhnd(4) port/region identifiers as follows:
[port] [addrspace] device0.0 0 device1.0 1 device1.1 2 device1.2 3
This allows the use of common (port,region) address map identifiers
across both bus types.
Depends on D6849