For amd64 kernels, repeat the 1GB mapping over the entire address space instead of just at 0GB and 1GB marks.  This gives more flexibility for the choice of KERNBASE.
For amd64 kernels, repeat the 1GB mapping over the entire address space
instead of just at 0GB and 1GB marks.  This gives more flexibility for
the choice of KERNBASE.

Approved by:	re (amd64 stuff)

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase