Bluetooth: Enable LE Long Term Key Request event only when supported

The support for LE encryption is optional and with that also the
LE Long Term Key Request event. If encryption is not supported, then
do not bother enabling this event.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

net/bluetooth/hci_core.c

@@ -1644,7 +1644,10 @@ static void hci_init3_req(struct hci_request *req, unsigned long opt)
 		u8 events[8];
 
 		memset(events, 0, sizeof(events));
-		events[0] = 0x1f;
+		events[0] = 0x0f;
+
+		if (hdev->le_features[0] & HCI_LE_ENCRYPTION)
+			events[0] |= 0x10;	/* LE Long Term Key Request */
 
 		/* If controller supports the Connection Parameters Request
 		 * Link Layer Procedure, enable the corresponding event.