arch: add support for cross-building um, User Mode Linux
Tools using tuxmake for building the kernel would need to duplicate some parts of it to support ARCH=um. Save them the hassle by providing um architecture support out-of-the-box.
Tools using tuxmake for building the kernel would need to duplicate some parts of it to support ARCH=um. Save them the hassle by providing um architecture support out-of-the-box.