Be consistant in the way that MSIZE, MCLSHIFT, MCLBYTES and NMBCLUSTERS
are defined.
Remove old VM constants from cesfic port.
Bump MSIZE to 256 on mipsco (the only one that wasn't already 256).
x86-64. Since there's no hardware available yet, this port is only
known to run on the Simics simulator for at the moment, and as such
uses the PC devices that it simulates for now. It will be developed
more (and cleaned up) as the hardware becomes available.
simonb