Bluetooth: ISO: Fix iso_sock_getsockopt for BT_DEFER_SETUP

BT_DEFER_SETUP shall be considered valid for all states except for
BT_CONNECTED as it is also used when initiated a connection rather then
only for BT_BOUND and BT_LISTEN.

Fixes: ccf74f23 ("Bluetooth: Add BTPROTO_ISO socket type")
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>