Add QLeController ctor that takes QBluetoothDeviceInfo

This ctor is required for OSX as the remote device address cannot be
retrieved. On other platforms this ctor is syntactic sugar to be able
to directly feed the device search results into the controller.

Change-Id: I4839a48861ebc625740e37aee5a779deeb32f96d
Reviewed-by: Timur Pocheptsov <Timur.Pocheptsov@digia.com>
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>