Now that all the targets are utilizing CPU_PC_{FETCH,STORE}, and the
cpu state is multicore, and the STATE_CPU defines match, we can move
it all to the common code.
Now that all targets have been converted to nrun, we can finally punt
this old inconsistent interface.
A few stray references to the old run were sprinkled about; clean them
up in the process.
We leave behind the run(1) man page mostly so that we get it updated for
the new nrun interface.
