In nRF_SDK_For_Thread_and_Zigbee, on the nordic BSP package following three-button functionalities are available:
#define BSP_BUTTON_ACTION_PUSH (APP_BUTTON_PUSH) /**< Represents pushing a button. See @ref bsp_button_action_t. */
#define BSP_BUTTON_ACTION_RELEASE (APP_BUTTON_RELEASE) /**< Represents releasing a button. See @ref bsp_button_action_t. */
#define BSP_BUTTON_ACTION_LONG_PUSH (3) /**< Represents pushing and holding a button for @ref BSP_LONG_PUSH_TIMEOUT_MS milliseconds. See also @ref bsp_button_action_t. */
In nRF_Connect_SDK, how can I implement BSP_BUTTON_ACTION_LONG_PUSH functionality?