PEP 510: add missing parameters to check() to support keywords

pep-0510.txt

@@ -235,11 +235,11 @@ Changes
   guards. It requires to implement a ``check()`` function, with an
   optional ``first_check()`` function. API:
 
-  * ``int check(PyObject *guard, PyObject **stack)``: return 1 on
-    success, 0 if the guard failed temporarely, -1 if the guard will
-    always fail
   * ``int first_check(PyObject *guard, PyObject *func)``: return 0 on
     success, -1 if the guard will always fail
+  * ``int check(PyObject *guard, PyObject **stack, int na, int nk)``:
+    return 1 on success, 0 if the guard failed temporarely, -1 if the
+    guard will always fail
 
 Microbenchmark on ``python3.6 -m timeit -s 'def f(): pass' 'f()'`` (best
 of 3 runs):