switch the rest of procfs lookups to d_splice_alias()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 2078e70..b77034a 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -256,8 +256,7 @@ struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry,
 		if (!inode)
 			return ERR_PTR(-ENOMEM);
 		d_set_d_op(dentry, &proc_misc_dentry_ops);
-		d_add(dentry, inode);
-		return NULL;
+		return d_splice_alias(inode, dentry);
 	}
 	read_unlock(&proc_subdir_lock);
 	return ERR_PTR(-ENOENT);