Bluetooth: Fix check for SSP when enabling SC

Bluetooth: Fix check for SSP when enabling SC

There's a check in set_secure_conn() that's supposed to ensure that SSP
is enabled before we try to request the controller to enable SC (since
SSP is a pre-requisite for it). However, this check only makes sense for
controllers actually supporting BR/EDR SC. If we have a 4.0 controller
we're only interested in the LE part of SC and should therefore not be
requiring SSP to be enabled. This patch adds an additional condition to
check for lmp_sc_capable(hdev) before requiring SSP to be enabled.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>