Bluetooth: controller: split: Refactor if_defines to is_enabled in lll.c

This commit refactors if defines to use the macro is_enabled,
for readability

Signed-off-by: Alexander Svensen <alsv@nordicsemi.no>

subsys/bluetooth/controller/ll_sw/nordic/lll/lll.c

@@ -221,16 +221,16 @@ void lll_disable(void *param)
 int lll_prepare_done(void *param)
 {
 #if defined(CONFIG_BT_CTLR_LOW_LAT) && \
-	(CONFIG_BT_CTLR_LLL_PRIO == CONFIG_BT_CTLR_ULL_LOW_PRIO)
+	    (CONFIG_BT_CTLR_LLL_PRIO == CONFIG_BT_CTLR_ULL_LOW_PRIO)
 	u32_t ret;
 
 	/* Ticker Job Silence */
 	ret = ticker_job_idle_get(TICKER_INSTANCE_ID_CTLR,
 				  TICKER_USER_ID_LLL,
 				  ticker_op_job_disable, NULL);
 
-	return ((ret == TICKER_STATUS_SUCCESS) || (ret == TICKER_STATUS_BUSY)) ?
-	       0 : -EFAULT;
+	return ((ret == TICKER_STATUS_SUCCESS) ||
+		(ret == TICKER_STATUS_BUSY)) ? 0 : -EFAULT;
 #else
 	return 0;
 #endif /* CONFIG_BT_CTLR_LOW_LAT */
@@ -258,10 +258,12 @@ int lll_done(void *param)
 			ull = HDR_ULL(((struct lll_hdr *)param)->parent);
 		}
 
-#if defined(CONFIG_BT_CTLR_LOW_LAT) && \
-	(CONFIG_BT_CTLR_LLL_PRIO == CONFIG_BT_CTLR_ULL_LOW_PRIO)
-		mayfly_enable(TICKER_USER_ID_LLL, TICKER_USER_ID_ULL_LOW, 1);
-#endif /* CONFIG_BT_CTLR_LOW_LAT */
+		if (IS_ENABLED(CONFIG_BT_CTLR_LOW_LAT) &&
+		    (CONFIG_BT_CTLR_LLL_PRIO == CONFIG_BT_CTLR_ULL_LOW_PRIO)) {
+			mayfly_enable(TICKER_USER_ID_LLL,
+				      TICKER_USER_ID_ULL_LOW,
+				      1);
+		}
 
 		DEBUG_RADIO_CLOSE(0);
 	} else {
@@ -408,12 +410,10 @@ static int prepare(lll_is_abort_cb_t is_abort_cb, lll_abort_cb_t abort_cb,
 #endif /* CONFIG_BT_CTLR_LOW_LAT */
 		int ret;
 
-#if defined(CONFIG_BT_CTLR_LOW_LAT)
-		/* early abort */
-		if (event.curr.param) {
+		if (IS_ENABLED(CONFIG_BT_CTLR_LOW_LAT) && event.curr.param) {
+			/* early abort */
 			event.curr.abort_cb(NULL, event.curr.param);
 		}
-#endif /* CONFIG_BT_CTLR_LOW_LAT */
 
 		/* Store the next prepare for deferred call */
 		ret = ull_prepare_enqueue(is_abort_cb, abort_cb, prepare_param,