This patch makes it possible to select the hugetlbfs page size at boot-time,
rather than at compile-time.  We believe we have resolved all the remaining
issues.  All critical speed path has been taken care of, i.e., vhpt handler
and context switch.  There should be no performance penalty with this dynamic
hugetlb page size feature.

We would like to thank Jack Steiner for his initiative on this feature
and his initial cool working patch.