gn build: Make setting llvm_enable_dia_sdk=true work

If this is set, %INCLUDE% must contain ".../DIA SDK/include"
and %LIB% must contain ".../DIA SKD/lib/amd64" (assuming you're doing a
64-bit build).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@359195 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed