[PATCH] ntfs build fix

*** Warning: "bit_spin_lock" [fs/ntfs/ntfs.ko] undefined!
*** Warning: "bit_spin_unlock" [fs/ntfs/ntfs.ko] undefined!

Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>