Make Linux client do FFS disklabel relocations.
Make Linux client do FFS disklabel relocations.

The only reason it didn't before was because we didn't have a "portable"
version of disklabel.h.  We have had that for quite some time now...

nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome,nmc-probe/emulab-nome