Bluetooth: Split ctrl init to BREDR and AMP parts

Current controller initialization is moved tp bredr_init and new
function added amp_init to handle later AMP init sequence. Current
AMP init sequence include Reset and Read Local Version.

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