Driver.cpp: Restore clang/Config/config.h to be included at last not to prevent llvm-config.h.

Or "llvm/Support/system_error.h" could not be compiled on mingw.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169354 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed