Bluetooth: Restrict high speed support to SSP enabled controllers

The support for Bluetooth High Speed can only be enabled on controllers
where also Secure Simple Pairing has been enabled. Trying to enable
high speed when SSP is disabled will result into an error. Disabling
SSP will at the same time disable high speed as well.

It is required to enforce this dependency on SSP since high speed
support is only defined for authenticated, unauthenticated and
debug link keys. These link key types require SSP.

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