Isolate the swapdev_vp "not quite" vnode in the only source file which needs it now that /dev/drum is gone.
Isolate the swapdev_vp "not quite" vnode in the only source file which
needs it now that /dev/drum is gone.

Reviewed by: eivind, peter

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