nfsd: nfsd_file_lease_notifier_call gets a file_lease as an argument

"data" actually refers to a file_lease and not a file_lock. Both structs
have their file_lock_core as the first field though, so this bug should
be harmless without struct randomization in play.

Reported-by: Florian Evers <[e-mail]>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219008
Fixes: 05580bbfc6bc ("nfsd: adapt to breakup of struct file_lock")
Signed-off-by: Jeff Layton <[e-mail]>
Tested-by: Florian Evers <[e-mail]>
Signed-off-by: Chuck Lever <[e-mail]>

fs/nfsd/filecache.c

···
 nfsd_file_lease_notifier_call(struct notifier_block *nb, unsigned long arg,
 			    void *data)
 {
-	struct file_lock *fl = data;
+	struct file_lease *fl = data;
 
 	/* Only close files for F_SETLEASE leases */
 	if (fl->c.flc_flags & FL_LEASE)