changes to make smp work in linux
console/console.c:
Remove Printed SimOS references and replace with M5
Rework the SMP stuff, so we don't trash any stacks, or what we
thought were stacks, but are actually other ppls memory.
console/dbmentry.s:
add a carefully crafted piece of assembly that doesn't use the stack,
so we don't clobber anthing in the time between when we are spinning
and when the OS tells us to go.
palcode/platform_m5.s:
add/fix code for IPI, multiprocessor interrupts (DIR), and initial
bootstrapping of the cpu