Bluetooth: Guarantee BR-EDR device will be registered as hci0

It's convenient to use the HCI device index the AMP controller id, but
the spec requires that an AMP controller never has id 0.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Acked-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>