extmod/moduos_dupterm: Don't swallow exceptions in dupterm's read()/write().

The idea is that if dupterm object can handle exceptions, it will handle
them itself. Otherwise, object state can be compromised and it's better
to terminate dupterm session. For example, disconnected socket will keep
throwing exceptions and dump messages about that.

extmod/moduos_dupterm.c

@@ -44,12 +44,9 @@ void mp_uos_dupterm_tx_strn(const char *str, size_t len) {
             mp_call_method_n_kw(1, 0, write_m);
             nlr_pop();
         } else {
-            // Temporarily disable dupterm to avoid infinite recursion
-            mp_obj_t save_term = MP_STATE_PORT(term_obj);
             MP_STATE_PORT(term_obj) = NULL;
-            mp_printf(&mp_plat_print, "dupterm: ");
+            mp_printf(&mp_plat_print, "dupterm: Exception in write() method, deactivating: ");
             mp_obj_print_exception(&mp_plat_print, nlr.ret_val);
-            MP_STATE_PORT(term_obj) = save_term;
         }
     }
 }