Don't include rel.h when relcache.h is sufficient

Trivial change to reduce exposure of rel.h.

src/backend/replication/logical/reorderbuffer.c

@@ -69,7 +69,7 @@
 #include "utils/combocid.h"
 #include "utils/memdebug.h"
 #include "utils/memutils.h"
-#include "utils/relcache.h"
+#include "utils/rel.h"
 #include "utils/relfilenodemap.h"
 #include "utils/tqual.h"
 

src/include/replication/reorderbuffer.h

@@ -10,13 +10,10 @@
 #define REORDERBUFFER_H
 
 #include "access/htup_details.h"
-
 #include "lib/ilist.h"
-
 #include "storage/sinval.h"
-
 #include "utils/hsearch.h"
-#include "utils/rel.h"
+#include "utils/relcache.h"
 #include "utils/snapshot.h"
 #include "utils/timestamp.h"