esp8266/moduos: Add dupterm_notify() function.

Should be called to notify that current dupterm object has more input
data to read.

esp8266/moduos.c

@@ -35,7 +35,7 @@
 #include "py/runtime.h"
 #include "extmod/misc.h"
 #include "genhdr/mpversion.h"
-#include "etshal.h"
+#include "esp_mphal.h"
 #include "user_interface.h"
 
 extern const mp_obj_type_t mp_fat_vfs_type;
@@ -110,12 +110,20 @@ STATIC mp_obj_t os_urandom(mp_obj_t num) {
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(os_urandom_obj, os_urandom);
 
+STATIC mp_obj_t os_dupterm_notify(mp_obj_t obj_in) {
+    (void)obj_in;
+    mp_hal_signal_dupterm_input();
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(os_dupterm_notify_obj, os_dupterm_notify);
+
 STATIC const mp_rom_map_elem_t os_module_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_uos) },
     { MP_ROM_QSTR(MP_QSTR_uname), MP_ROM_PTR(&os_uname_obj) },
     { MP_ROM_QSTR(MP_QSTR_urandom), MP_ROM_PTR(&os_urandom_obj) },
     #if MICROPY_PY_OS_DUPTERM
     { MP_ROM_QSTR(MP_QSTR_dupterm), MP_ROM_PTR(&mp_uos_dupterm_obj) },
+    { MP_ROM_QSTR(MP_QSTR_dupterm_notify), MP_ROM_PTR(&os_dupterm_notify_obj) },
     #endif
     #if MICROPY_VFS_FAT
     { MP_ROM_QSTR(MP_QSTR_VfsFat), MP_ROM_PTR(&mp_fat_vfs_type) },