Typo in comment in nbtree.h

Hi

Following along with a btree bug report, I saw a typo "referencd" in a
comment.  Also "we've" seems a bit odd here, but maybe it's just me.
Maybe it should be like this?

--- a/src/include/access/nbtree.h
+++ b/src/include/access/nbtree.h
@@ -522,7 +522,7 @@ typedef struct BTScanPosData       Buffer          buf;                    /* if valid, the
buffer is pinned */
       XLogRecPtr      lsn;                    /* pos in the WAL
stream when page was read */
-       BlockNumber currPage;           /* page we've referencd by
items array */
+       BlockNumber currPage;           /* page referenced by items array */       BlockNumber nextPage;           /*
page'sright link when we
 
scanned it */
       /*

-- 
Thomas Munro
http://www.enterprisedb.com