Bluetooth: Don't send ERTM configuration option when disabled

When ERTM support is disabled, then do not even send ERTM configuration
option even if the remote side supports it.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

net/bluetooth/l2cap_core.c

@@ -3234,6 +3234,9 @@ static int l2cap_build_conf_req(struct l2cap_chan *chan, void *data)
 
 	switch (chan->mode) {
 	case L2CAP_MODE_BASIC:
+		if (disable_ertm)
+			break;
+
 		if (!(chan->conn->feat_mask & L2CAP_FEAT_ERTM) &&
 		    !(chan->conn->feat_mask & L2CAP_FEAT_STREAMING))
 			break;