Adding support for programming with onboard USB JTAG.
Adding support for programming with onboard USB JTAG.

There are two options;

 * Using the proprietary Digilent Adept Utilities.
 * Using the FOSS fpgalink tool.

To use Digilent Adept Utilities, add the following to your ./make.py command;
 -Op programmer adept

To use FPGALink, add the following to your ./make.py command;
 -Op programmer fpgalink

mithro/HDMI2USB-litex-firmware,cr1901/HDMI2USB-litex-firmware,cr1901/HDMI2USB-litex-firmware,cr1901/HDMI2USB-litex-firmware,mithro/HDMI2USB-litex-firmware,mithro/HDMI2USB-litex-firmware,cr1901/HDMI2USB-litex-firmware,mithro/HDMI2USB-litex-firmware