Fixes attribute error in keypad indev driver

Author: kdschlosser

api_drivers/py_api_drivers/frozen/indev/keypad_framework.py

@@ -11,7 +11,7 @@ def __init__(self):  # NOQA
 
         super().__init__()
         self._set_type(lv.INDEV_TYPE.KEYPAD)  # NOQA
-        indev_drv.enable(True)  # NOQA
+        self._indev_drv.enable(True)  # NOQA
 
     def _get_key(self):
         # this method needs to be overridden.