Bluetooth: Use correct flags for checking HCI_SSP_ENABLED bit

This patch uses the correct flags for checking the HCI_SSP_ENABLED bit.
Without this authentication request was not being initiated.

Signed-off-by: Hemant Gupta <hemant.gupta@stericsson.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>