radv: a conformant Vulkan driver under X.org

If you take a look at the conformant vulkan list, you will see entry 220 - Software in the Public Interest, Inc. 2017-10-04 Vulkan_1_0 220. This is radv, and this is the first conformance submission done under the X.org (SPI) membership of the Khronos adopter program. A major milestone has been reached and radv is now a conformant Vulkan driver.