pg_stat_statements: Fix second comment related to entry resets

This should have been part of dc73db6, but it got lost in the mix.
Oversight in 6b4d23f.

Author: Japin Li
Discussion: https://postgr.es/m/MEYP282MB1669FC91C764E277821936D3B624A@MEYP282MB1669.AUSP282.PROD.OUTLOOK.COM
Backpatch-through: 14

contrib/pg_stat_statements/pg_stat_statements.c

@@ -2518,7 +2518,9 @@ entry_reset(Oid userid, Oid dbid, uint64 queryid)
 		key.dbid = dbid;
 		key.queryid = queryid;
 
-		/* Remove the key if it exists, starting with the top-level entry  */
+		/*
+		 * Remove the key if it exists, starting with the non-top-level entry.
+		 */
 		key.toplevel = false;
 		entry = (pgssEntry *) hash_search(pgss_hash, &key, HASH_REMOVE, NULL);
 		if (entry)				/* found */