Split the driver into the core functionality part (sys/dev/tsec/if_tsec.c) and
the bus attachment (sys/dev/tsec/if_tsec_ocp.c).
This lets better integrate and maintain the driver in other environments with
different attachment abstractions (there is at least one other FreeBSD port --
MPC83xx -- which uses this TSEC driver, but with different local bus model
i.e. some OF derivative). While there, clean up and fix minor cosmetics.
Obtained from: Semihalf
321e12c82e