Bluetooth: Fix encryption key size for peripheral role

This patch fixes the connection encryption key size information when
the host is playing the peripheral role. We should set conn->enc_key_
size in hci_le_ltk_request_evt, otherwise it is left uninitialized.

Cc: Stable <stable@vger.kernel.org>
Signed-off-by: NAndre Guedes <andre.guedes@openbossa.org>
Signed-off-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>

net/bluetooth/hci_event.c

@@ -3561,6 +3561,8 @@ static void hci_le_ltk_request_evt(struct hci_dev *hdev, struct sk_buff *skb)
 	else
 		conn->pending_sec_level = BT_SECURITY_MEDIUM;
 
+	conn->enc_key_size = ltk->enc_size;
+
 	hci_send_cmd(hdev, HCI_OP_LE_LTK_REPLY, sizeof(cp), &cp);
 
 	if (ltk->type & HCI_SMP_STK) {