Do not hardcode the list of 64-bit CPUs.  Use sizeof(void *) to
compute it.  Renaming it to HOST_LONG_BITS to HOST_POINTER_BITS
is left for later.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>