Successful compile (with a few warnings)

- Created a successful compile, CMake made stuff a bit more complicated than I initially thought but it looks like it works well
- Added platform.h from alibc which defines restrict if available
- Fixed compile errors in string.c
- Fixed errors in profile_detection.cmake where certain variables were not passed to the parent scope
- Created flags.cmake files (some are stubs)
- Created linker script
- Modified CMake to support AT&T style Assembly