Simplify some things to use libufs-provided functionality here, such as the version of UFS on a disk, and bread() instead of other types of idiocy.
Simplify some things to use libufs-provided functionality here, such as the
version of UFS on a disk, and bread() instead of other types of idiocy.

Obtained from:	jmallett_libufs Perforce branch.

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