py/objtype: Make sure mp_binary_op_method_name has full size again.

After recent refactorings to mp_binary_op_t, and make it future refactoring
proof for now, at the cost of extra element in the array.

py/objtype.c

@@ -453,7 +453,7 @@ const qstr mp_binary_op_method_name[] = {
     /*
     MP_BINARY_OP_IS,
     */
-    [MP_BINARY_OP_EXCEPTION_MATCH] = MP_QSTR_, // not implemented, used to make sure array has full size
+    [MP_BINARY_OP_LAST] = 0, // used to make sure array has full size, TODO: FIXME
 };
 
 STATIC mp_obj_t instance_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {

py/runtime0.h

@@ -103,6 +103,8 @@ typedef enum {
     // just identify special methods.
 
     MP_BINARY_OP_DIVMOD, // not emitted by the compiler but supported by the runtime
+
+    MP_BINARY_OP_LAST,
 } mp_binary_op_t;
 
 typedef enum {