Commit ff03261adc ('Bluetooth: Fix
sending a HCI Authorization Request over LE links', commit
d8343f1257 upstream) added an
call to smp_conn_security() from hci_conn_security(). The
former is only defined if CONFIG_BT_L2CAP=y.
This is not required in mainline since commit
f1e91e1640 ('Bluetooth: Always compile
SCO and L2CAP in Bluetooth Core') removed that option.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>