Bluetooth: Provide defaults for LE advertising interval

Store the default values for minimum and maximum advertising interval
with all the other controller defaults. These vaules are sent to the
adapter whenever advertising is (re)enabled.

Signed-off-by: Georg Lukas <georg@op-co.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --cc include/net/bluetooth/hci_core.h
Simple merge

diff --cc net/bluetooth/hci_core.c
Simple merge

diff --cc net/bluetooth/mgmt.c
Simple merge