MOUNT_LFS to "lfs" in one place. The merge was painful because it
conflicted with cosmetic FreeBSD changes. lfs_cleanerd still compiles
cleanly but has aproximately the same chance of working as before (0).
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.