[CMake] llvm-lto2 depends on intrinsics_gen

llvm-lto2.cpp has the following include chain:

llvm/LTO/Caching.h
llvm/LTO/LTO.h
llvm/CodeGen/Analysis.h
llvm/IR/CallSite.h
llvm/IR/Attributes.h
llvm/IR/Attributes.gen

This means llvm-lto2 needs to depend on intrinsics_gen.

llvm-svn: 287434