When an adapter is removed (hci_unregister_dev) any pending mgmt
commands for that adapter should get the appropriate INVALID_INDEX
response. Since hci_unregister_dev() calls hci_dev_do_close() first
that'd so far have caused "not powered" responses to be sent.

Skipping the HCI_UNREGISTER case in mgmt_powered() is also not a
solution since before reaching the mgmt_index_removed() stage any
hci_conn callbacks (e.g. used by pairing) will get called, thereby
causing "disconnected" status responses to be sent.

The fix that covers all scenarios is to handle both INVALID_INDEX and
NOT_POWERED responses through the mgmt_powered() function. The
INVALID_INDEX response sending from mgmt_index_removed() is left
untouched since there are a couple of places not related to powering off
or removing an adapter that call it (e.g. configuring a new bdaddr).
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>