Remove unused arguments in two GiST subroutines

These arguments became unused in commit 2c03216d83.  Noticed while
skimming code for unrelated development.

This is cosmetic, so no backpatch.

src/backend/access/gist/gist.c

@@ -467,7 +467,7 @@ gistplacetopage(Relation rel, Size freespace, GISTSTATE *giststate,
 
 		/* Write the WAL record */
 		if (RelationNeedsWAL(rel))
-			recptr = gistXLogSplit(rel->rd_node, blkno, is_leaf,
+			recptr = gistXLogSplit(is_leaf,
 								   dist, oldrlink, oldnsn, leftchildbuf,
 								   markfollowright);
 		else
@@ -523,7 +523,7 @@ gistplacetopage(Relation rel, Size freespace, GISTSTATE *giststate,
 				ndeloffs = 1;
 			}
 
-			recptr = gistXLogUpdate(rel->rd_node, buffer,
+			recptr = gistXLogUpdate(buffer,
 									deloffs, ndeloffs, itup, ntup,
 									leftchildbuf);
 
@@ -1541,7 +1541,7 @@ gistvacuumpage(Relation rel, Page page, Buffer buffer)
 		{
 			XLogRecPtr	recptr;
 
-			recptr = gistXLogUpdate(rel->rd_node, buffer,
+			recptr = gistXLogUpdate(buffer,
 									deletable, ndeletable,
 									NULL, 0, InvalidBuffer);
 

src/backend/access/gist/gistvacuum.c

@@ -223,7 +223,7 @@ gistbulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
 				{
 					XLogRecPtr	recptr;
 
-					recptr = gistXLogUpdate(rel->rd_node, buffer,
+					recptr = gistXLogUpdate(buffer,
 											todelete, ntodelete,
 											NULL, 0, InvalidBuffer);
 					PageSetLSN(page, recptr);

src/backend/access/gist/gistxlog.c

@@ -323,7 +323,7 @@ gist_xlog_cleanup(void)
  * Write WAL record of a page split.
  */
 XLogRecPtr
-gistXLogSplit(RelFileNode node, BlockNumber blkno, bool page_is_leaf,
+gistXLogSplit(bool page_is_leaf,
 			  SplitedPageLayout *dist,
 			  BlockNumber origrlink, GistNSN orignsn,
 			  Buffer leftchildbuf, bool markfollowright)
@@ -387,7 +387,7 @@ gistXLogSplit(RelFileNode node, BlockNumber blkno, bool page_is_leaf,
  * to log the whole buffer contents instead.
  */
 XLogRecPtr
-gistXLogUpdate(RelFileNode node, Buffer buffer,
+gistXLogUpdate(Buffer buffer,
 			   OffsetNumber *todelete, int ntodelete,
 			   IndexTuple *itup, int ituplen,
 			   Buffer leftchildbuf)