Bluetooth: controller: df: Config help corrction correction

Correct names of kconfig entries to mach to style of other entries.
Style correction in hci.c. Use the same approach of checking if
Kconfig entry is enabled.

Signed-off-by: Piotr Pryga <[email protected]>

Author: ppryga-nordic

subsys/bluetooth/controller/Kconfig.df

@@ -38,7 +38,7 @@ config BT_CTLR_DF_CTE_TX
 	  controller.
 
 config BT_CTLR_DF_ANT_SWITCH_1US
-	bool "Enable support for 1us antenna switching slots"
+	bool "Enable support for 1us antenna switch slots"
 	depends on BT_CTLR_DF_ANT_SWITCH_1US_SUPPORT
 	default y
 	help

subsys/bluetooth/controller/hci/hci.c

@@ -3504,7 +3504,7 @@ static int controller_cmd_handle(uint16_t  ocf, struct net_buf *cmd,
 		le_read_tx_power(cmd, evt);
 		break;
 
-#if defined(CONFIG_BT_CTLR_DF)
+#if IS_ENABLED(CONFIG_BT_CTLR_DF)
 #if IS_ENABLED(CONFIG_BT_CTLR_DF_ADV_CTE_TX)
 	case BT_OCF(BT_HCI_OP_LE_SET_CL_CTE_TX_PARAMS):
 		le_df_set_cl_cte_tx_params(cmd, evt);