tests: Bluetooth: llpc: Add at-instant conn evt proc in collision UT

Unit tests reposnsible for verification of collisions mitigation
didn't have handling for delayed completion of PHY Update control
procedure. The PHY Update is completed on event generated when
"at-instant" connection event is on air.

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

tests/bluetooth/controller/ctrl_collision/src/main.c

@@ -328,7 +328,7 @@ void test_phy_update_central_rem_collision(void)
 	struct pdu_data_llctrl_phy_upd_ind ind_1 = { .instant = 7,
 						     .c_to_p_phy = 0,
 						     .p_to_c_phy = PHY_2M };
-	struct pdu_data_llctrl_phy_upd_ind ind_2 = { .instant = 14,
+	struct pdu_data_llctrl_phy_upd_ind ind_2 = { .instant = 15,
 						     .c_to_p_phy = PHY_2M,
 						     .p_to_c_phy = 0 };
 	uint16_t instant;
@@ -400,6 +400,15 @@ void test_phy_update_central_rem_collision(void)
 	/* Prepare */
 	event_prepare(&conn);
 
+	/* Tx Queue should NOT have a LL Control PDU */
+	lt_rx_q_is_empty(&conn);
+
+	/* Done */
+	event_done(&conn);
+
+	/* Prepare */
+	event_prepare(&conn);
+
 	/* Tx Queue should have one LL Control PDU */
 	lt_rx(LL_PHY_REQ, &conn, &tx, &req_central);
 	lt_rx_q_is_empty(&conn);