o use mtree code directly from ../mtree; s/spec(fp)/mtree_readspec(fp)/
(assume this will eventually go in usr.sbin)
o nuke st_rdev use; there's no reason to create filesystems with device nodes
o shim missing compat bits for inotype and nodetoino
o remove now unneeded compat/mtree bits, pack_dev.?, and stat_flags.?
o temporarily move getid.c code up to compat to keep this building
