Obsolete reference to pg_relation in comment

Hi hackers,

Triggered by a discussion on IRC, I noticed that there's a stray
reference to pg_relation in a comment that was added long after it was
renamed to pg_class.  Here's a patch to bring that up to speed.

- ilmari

From e395f8cb293f674f45eb3847534de07c7124e738 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dagfinn=20Ilmari=20Manns=C3=A5ker?= <ilmari@ilmari.org>
Date: Wed, 26 Jul 2023 18:31:51 +0100
Subject: [PATCH] Fix obsolete reference to pg_relation in comment

pg_relation was renamed to pg_class in 1991, but this comment (added
in 2004) missed the memo
---
 src/backend/storage/large_object/inv_api.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/backend/storage/large_object/inv_api.c b/src/backend/storage/large_object/inv_api.c
index 84e543e731..a56912700b 100644
--- a/src/backend/storage/large_object/inv_api.c
+++ b/src/backend/storage/large_object/inv_api.c
@@ -59,7 +59,7 @@ bool        lo_compat_privileges;
 
 /*
  * All accesses to pg_largeobject and its index make use of a single Relation
- * reference, so that we only need to open pg_relation once per transaction.
+ * reference, so that we only need to open pg_class once per transaction.
  * To avoid problems when the first such reference occurs inside a
  * subtransaction, we execute a slightly klugy maneuver to assign ownership of
  * the Relation reference to TopTransactionResourceOwner.
-- 
2.39.2