Bluetooth: Simplify a the connection type handling

Now that we have separate ways of doing connections for each link type,
we can do better than an "if" statement to handle each link type.

Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@openbossa.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>