Use the right predicate in ->atomic_open() instances

->atomic_open() can be given an in-lookup dentry *or* a negative one
found in dcache.  Use d_in_lookup() to tell one from another, rather
than d_unhashed().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index d8015a0..3d5eb5e 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -1504,7 +1504,7 @@
 
 	/* NFS only supports OPEN on regular files */
 	if ((open_flags & O_DIRECTORY)) {
-		if (!d_unhashed(dentry)) {
+		if (!d_in_lookup(dentry)) {
 			/*
 			 * Hashed negative dentry with O_DIRECTORY: dentry was
 			 * revalidated and is fine, no need to perform lookup