Function connect_map 

pub async fn connect_map(
    addr: Address,
    channel: u8,
    bt_gate: Duration,
) -> Result<MapClient<Stream>, SessionError>

RFCOMM connect to addr:channel (gating on BT_CONNECTED up to bt_gate) then establish_map_session.

Errors

Returns SessionError::Transport on RFCOMM failure or BT_CONNECTED timeout, SessionError::Map on OBEX failure.