called "MACHINE_NEW_NONCONGIG". this is required for UVM, the new VM
system (also written by chuck) that is coming soon. adds new functions:
vm_page_physload() -- tell the VM system about an area of memory.
vm_physseg_find() -- returns index in vm_physmem array that this
address is in.
and several new versions of old functions/macros defined in vm_page.h.
this is the MI portion. sparc, and then later i386 portions to come.
all other ports need to change to this ASAP! (alpha is already being
worked on)