Bluetooth: controller: Fix llcp_rx check assert

If LL Connection Parameter Request or LL Connection Update
or LL PHY Update procedure is started by the local device
while a LL Length Update Request PDU has been sent by peer
then a Rx node has been stored in the llcp_rx place holder
for generation of Length Update procedure complete.

The failing assert check is incorrect in the above scenario
hence remove. Instead a missing append of the allocated Rx
node to the llcp_rx list has been added to the controller
implementation.

This issue relates to commit d12c53f ("Bluetooth:
controller: split: Fix missing data len update event").

Signed-off-by: Vinayak Kariappa Chettimada <[email protected]>

Author: cvinayak

subsys/bluetooth/controller/ll_sw/ull_conn.c

@@ -2125,8 +2125,6 @@ static inline int event_conn_upd_prep(struct ll_conn *conn, u16_t lazy,
 		struct node_rx_pdu *rx;
 		struct node_tx *tx;
 
-		LL_ASSERT(!conn->llcp_rx);
-
 		rx = ll_pdu_rx_alloc_peek(1);
 		if (!rx) {
 			return -ENOBUFS;
@@ -2138,6 +2136,7 @@ static inline int event_conn_upd_prep(struct ll_conn *conn, u16_t lazy,
 		}
 
 		(void)ll_pdu_rx_alloc();
+		rx->hdr.link->mem = conn->llcp_rx;
 		conn->llcp_rx = rx;
 
 		pdu_ctrl_tx = (void *)tx->pdu;
@@ -3463,8 +3462,6 @@ static inline void event_phy_upd_ind_prep(struct ll_conn *conn,
 		struct node_rx_pdu *rx;
 		struct node_tx *tx;
 
-		LL_ASSERT(!conn->llcp_rx);
-
 #if defined(CONFIG_BT_CTLR_DATA_LENGTH)
 		rx = ll_pdu_rx_alloc_peek(2);
 #else /* !CONFIG_BT_CTLR_DATA_LENGTH */