instead of puffs_start(). Get completely rid of puffs_start(), as
everything it used to do is now handled by the mount routine.
Introduce an optional pre-mount call puffs_setrootinfo() for setting
non-default root node information. As the old puffs_mount() is
now virtually useless, say byebye to it and rename the old
puffs_domount() to puffs_mount(), but add a root cookie parameter
to compensate for the late puffs_start().
c7561a8e7c