examples: use YYLOCATION_PRINT

* examples/c/bistromathic/parse.y, examples/c/glr/c++-types.y,
* examples/c/lexcalc/parse.y: Don't use the private internal detail
`YY_LOCATION_PRINT`, use `YYLOCATION_PRINT`.

examples/c/lexcalc/parse.y

@@ -120,7 +120,7 @@ exp:
 
 void yyerror (YYLTYPE *loc, const char *msg)
 {
-  YY_LOCATION_PRINT (stderr, *loc);
+  YYLOCATION_PRINT (stderr, loc);
   fprintf (stderr, ": %s\n", msg);
 }