Bluetooth: controller: split: Port Enc setup to be queueable

Port the fix for the controller implementation to make start
encryption queueable if there is any control procedure in
progress.

Refer to #15335.
Relates to #15335, #15186, #15958 and #14636.

Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>

Author: cvinayak

subsys/bluetooth/controller/ll_sw/ull_adv.c

@@ -564,11 +564,6 @@ u8_t ll_adv_enable(u8_t enable)
 		conn_lll->nesn = 0;
 		conn_lll->empty = 0;
 
-#if defined(CONFIG_BT_CTLR_LE_ENC)
-		conn_lll->enc_rx = 0;
-		conn_lll->enc_tx = 0;
-#endif /* CONFIG_BT_CTLR_LE_ENC */
-
 #if defined(CONFIG_BT_CTLR_DATA_LENGTH)
 		conn_lll->max_tx_octets = PDU_DC_PAYLOAD_SIZE_MIN;
 		conn_lll->max_rx_octets = PDU_DC_PAYLOAD_SIZE_MIN;
@@ -627,7 +622,10 @@ u8_t ll_adv_enable(u8_t enable)
 		conn->llcp_terminate.node_rx.hdr.link = link;
 
 #if defined(CONFIG_BT_CTLR_LE_ENC)
-		conn->pause_tx = conn->pause_rx = conn->refresh = 0;
+		conn_lll->enc_rx = conn_lll->enc_tx = 0U;
+		conn->llcp_enc.req = conn->llcp_enc.ack = 0U;
+		conn->llcp_enc.pause_tx = conn->llcp_enc.pause_rx = 0U;
+		conn->llcp_enc.refresh = 0U;
 #endif /* CONFIG_BT_CTLR_LE_ENC */
 
 #if defined(CONFIG_BT_CTLR_CONN_PARAM_REQ)