[gn build] Add build files for llvm-cat, llvm-lto, llvm-lto2, llvm-modextract, llvm-profdata, llvm-symbolizer

These are the llvm/tools needed by check-clang.

Differential Revision: https://reviews.llvm.org/D56018


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349989 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed