Fix typo in pathnode.c

Author: Amit Langote
Discussion: https://postgr.es/m/CA+HiwqFhZ6ABoz-i=JZ5wMMyz-orx4asjR0og9qBtgEwOww6Yg@mail.gmail.com

src/backend/optimizer/util/pathnode.c

@@ -775,7 +775,7 @@ add_partial_path(RelOptInfo *parent_rel, Path *new_path)
 		/* Compare pathkeys. */
 		keyscmp = compare_pathkeys(new_path->pathkeys, old_path->pathkeys);
 
-		/* Unless pathkeys are incompable, keep just one of the two paths. */
+		/* Unless pathkeys are incompatible, keep just one of the two paths. */
 		if (keyscmp != PATHKEYS_DIFFERENT)
 		{
 			if (new_path->total_cost > old_path->total_cost * STD_FUZZ_FACTOR)