Catalina 10.15.1 add AMD Navi RDNA support

Apple today seeded the first beta of an upcoming macOS Success' href='/2020/12/install-macos-catalina-on-supported-pc.html'>Catalina 10.15.1 update to developers.

Support has been added for the AMD Navi RDNA architecture.

https://developer.apple.com/documentation/macos_release_notes/macos_catalina_10_15_1_beta_release_notes

Good news to RX 5700/XT and RX 5500.

Author: @chevalierw