Bluetooth: L2CAP: Fix type confusion in l2cap_ecred_reconf_rsp()

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: Fix type confusion in l2cap_ecred_reconf_rsp() l2cap_ecred_reconf_rsp() casts the incoming data to struct l2cap_ecred_conn_rsp (the ECRED *connection* response, 8 bytes with result at offset 6) instead of struct l2cap_ecred_reconf_rsp (2 bytes with result at offset 0). This causes two problems: - The sizeof(*rsp) length check requires 8 bytes instead of the correct 2, so valid L2CAP_ECRED_RECONF_RSP packets are rejected with -EPROTO. - rsp->result reads from offset 6 instead of offset 0, returning wrong data when the packet is large enough to pass the check. Fix by using the correct type. Also pass the already byte-swapped result variable to BT_DBG instead of the raw __le16 field.