Fixed double counting of runtime after a process exits.  The last timeslice of the exiting process was counted for both the exiting process and the next process to run if the next process runs immediately.
Fixed double counting of runtime after a process exits.  The last
timeslice of the exiting process was counted for both the exiting
process and the next process to run if the next process runs
immediately.

Broken in:	mostly in kern_clock.c rev.1.70 (1998/05/28)

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase