pic16bit/main: Make nlr_jump_fail never return.

pic16bit/main.c

@@ -111,6 +111,7 @@ mp_obj_t mp_builtin_open(uint n_args, const mp_obj_t *args, mp_map_t *kwargs) {
 MP_DEFINE_CONST_FUN_OBJ_KW(mp_builtin_open_obj, 1, mp_builtin_open);
 
 void nlr_jump_fail(void *val) {
+    while (1);
 }
 
 void NORETURN __fatal_error(const char *msg) {