locks: set fl_owner for leases to filp instead of current->files

Like flock locks, leases are owned by the file description. Now that the
i_have_this_lease check in __break_lease is gone, we don't actually use
the fl_owner for leases for anything. So, it's now safe to set this more
appropriately to the same value as the fl_file.

While we're at it, fix up the comments over the fl_owner_t definition
since they're rather out of date.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
diff --git a/fs/locks.c b/fs/locks.c
index aed4a95..314135a 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -465,7 +465,7 @@
 	if (assign_type(fl, type) != 0)
 		return -EINVAL;
 
-	fl->fl_owner = current->files;
+	fl->fl_owner = filp;
 	fl->fl_pid = current->tgid;
 
 	fl->fl_file = filp;