kextsymboltool port for linux
Add missing __int64_t and __uint64_t for i386
'uname -p' does not always return processor architecture.
Add unifdef to dependencies, needed when installing XNU headers
Fix c declaration bug that causes build failure on later versions of clang
Small workaround for users building on x64 systems
Move prebuilt libclang_rt.cc_kext.a installation from clean to install target