Eliminate unnecessary cache and TLB flushes by pmap_change_attr().  (This optimization was implemented in the amd64 version roughly 1 year ago.)
Eliminate unnecessary cache and TLB flushes by pmap_change_attr().  (This
optimization was implemented in the amd64 version roughly 1 year ago.)

Approved by:	re (kensmith)

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