Update the comment in rmgrlist.h to match it to the code.

Author: Hayato Kuroda
Reviwed-by: Amit Kapila
Discussion: https://postgr.es/m/TYAPR01MB58665F20F412EDF27B0759CFF5769@TYAPR01MB5866.jpnprd01.prod.outlook.com

Author: Amit Kapila

src/include/access/rmgrlist.h

@@ -24,7 +24,7 @@
  * Changes to this list possibly need an XLOG_PAGE_MAGIC bump.
  */
 
-/* symbol name, textual name, redo, desc, identify, startup, cleanup */
+/* symbol name, textual name, redo, desc, identify, startup, cleanup, mask, decode */
 PG_RMGR(RM_XLOG_ID, "XLOG", xlog_redo, xlog_desc, xlog_identify, NULL, NULL, NULL, xlog_decode)
 PG_RMGR(RM_XACT_ID, "Transaction", xact_redo, xact_desc, xact_identify, NULL, NULL, NULL, xact_decode)
 PG_RMGR(RM_SMGR_ID, "Storage", smgr_redo, smgr_desc, smgr_identify, NULL, NULL, NULL, NULL)