Fix oversight in pg_dump's handling of extension configuration tables.

If an extension has not been selected to be dumped (perhaps because of
a --schema or --table switch), the contents of its configuration tables
surely should not get dumped either.  Per gripe from
Hubert Depesz Lubaczewski.

src/bin/pg_dump/pg_dump.c

@@ -13794,13 +13794,18 @@ getExtensionMembership(ExtensionInfo extinfo[], int numExtensions)
 	 */
 	for (i = 0; i < numExtensions; i++)
 	{
-		char	   *extconfig = extinfo[i].extconfig;
-		char	   *extcondition = extinfo[i].extcondition;
+		ExtensionInfo *curext = &(extinfo[i]);
+		char	   *extconfig = curext->extconfig;
+		char	   *extcondition = curext->extcondition;
 		char	  **extconfigarray = NULL;
 		char	  **extconditionarray = NULL;
 		int			nconfigitems;
 		int			nconditionitems;
 
+		/* Tables of not-to-be-dumped extensions shouldn't be dumped */
+		if (!curext->dobj.dump)
+			continue;
+
 		if (parsePGArray(extconfig, &extconfigarray, &nconfigitems) &&
 		  parsePGArray(extcondition, &extconditionarray, &nconditionitems) &&
 			nconfigitems == nconditionitems)