Hello.
It is not recommended to run an older Vivado on a recent OS, instead use a more recent Xilinx Vivado Lab release, or use a slightly older OS version -- for example via a virtual machine (VM).
In order to use the JTAG interface, you will need to install the Digilent Cable Driver. It is included with the Xilinx Vivado Lab Edition package.
Navigate to the folder /opt/Xilinx/Vivado_Lab/2015.4/data/xicom/cable_drivers/lin64/install_script/install_drivers, and run the installer script.
cd /opt/Xilinx/Vivado_Lab/2015.4/data/xicom/cable_drivers/lin64/install_script/install_drivers
sudo ./install_digilent.sh
Find instructions in the bellow:
X300/X310 Device Recovery - Ettus Knowledge Base
Regards.
