Conditional mntput() moved into __do_follow_link().  There it collapses with
unconditional mntget() on the same sucker, closing another too-early-mntput()
race.
Signed-off-by: NAl Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>