[PATCH] fuse: minor cleanup in fuse_dentry_revalidate

Remove unneeded code from fuse_dentry_revalidate().  This made some sense
while the validity time could wrap around, but now it's a very obvious no-op.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>