[PATCH] ufs: little directory lookup optimization

This patch make little optimization of ufs_find_entry like "ext2" does.  Save
number of page and reuse it again in the next call.

Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>