Bluetooth: MGMT: Fix LE simultaneous roles UUID if not supported

If controller/driver don't support LE simultaneous roles its UUID shall
be omitted when responding to MGMT_OP_READ_EXP_FEATURES_INFO.

This also rework the support introducing HCI_LE_SIMULTANEOUS_ROLES flag
so it can be detected when userspace wants to use or not.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>