vmm(4): report PA bits in CPUID[0x80000008]
We were previously hiding this information from the guest but there
really isn't a reason to do that. Hiding this value limits the PA size
to 36 bits (64GB), which I discovered the hard way when creating some
big VMs recently.
Sprinkle a few ifdefs for _LOCORE and _KERNEL and reorder a few lines
so that pmap.h can be included as part of the mmap_hint regression test.
From Moritz Buhl