For libkern and libsa on NetBSD, the normal system headers can't be
used. Adjust.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@196292 91177308-0d34-0410-b5e6-96231b3b80d8
GC empty directory


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@196293 91177308-0d34-0410-b5e6-96231b3b80d8