[nrf fromtree] Bluetooth: Controller: nRF: Support MDK 8.68

TASK_SHUTDOWN was deprecated in newer SOCs and now removed
in MDK 8.68 (nrfx 3.9.0)

Signed-off-by: Alberto Escolar Piedras <[email protected]>
Signed-off-by: Vinayak Kariappa Chettimada <[email protected]>
(cherry picked from commit 4294814)

Author: aescolar

subsys/bluetooth/controller/ll_sw/nordic/hal/nrf5/radio/radio.c

@@ -1696,11 +1696,15 @@ uint32_t radio_tmr_start_get(void)
 void radio_tmr_stop(void)
 {
 	nrf_timer_task_trigger(EVENT_TIMER, NRF_TIMER_TASK_STOP);
+#if defined(TIMER_TASKS_SHUTDOWN_TASKS_SHUTDOWN_Msk)
 	nrf_timer_task_trigger(EVENT_TIMER, NRF_TIMER_TASK_SHUTDOWN);
+#endif
 
 #if !defined(CONFIG_BT_CTLR_TIFS_HW)
 	nrf_timer_task_trigger(SW_SWITCH_TIMER, NRF_TIMER_TASK_STOP);
+#if defined(TIMER_TASKS_SHUTDOWN_TASKS_SHUTDOWN_Msk)
 	nrf_timer_task_trigger(SW_SWITCH_TIMER, NRF_TIMER_TASK_SHUTDOWN);
+#endif
 #endif /* !CONFIG_BT_CTLR_TIFS_HW */
 
 #if defined(CONFIG_SOC_COMPATIBLE_NRF54LX)