IWYU for llvm-config.h in clang. See r331124 for details.

llvm-svn: 331177
diff --git a/clang/lib/Driver/Driver.cpp b/clang/lib/Driver/Driver.cpp
index c119f33..f41fd56 100644
--- a/clang/lib/Driver/Driver.cpp
+++ b/clang/lib/Driver/Driver.cpp
@@ -57,6 +57,7 @@
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringSet.h"
 #include "llvm/ADT/StringSwitch.h"
+#include "llvm/Config/llvm-config.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Option/OptSpecifier.h"
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 77bbc60..3dc657e 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -30,6 +30,7 @@
 #include "clang/Driver/SanitizerArgs.h"
 #include "clang/Driver/XRayArgs.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/Config/llvm-config.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Support/Compression.h"
diff --git a/clang/lib/Driver/ToolChains/MSVC.cpp b/clang/lib/Driver/ToolChains/MSVC.cpp
index a7fbfbb..d903d2f 100644
--- a/clang/lib/Driver/ToolChains/MSVC.cpp
+++ b/clang/lib/Driver/ToolChains/MSVC.cpp
@@ -19,7 +19,6 @@
 #include "clang/Driver/SanitizerArgs.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringSwitch.h"
-#include "llvm/Config/llvm-config.h"
 #include "llvm/Option/Arg.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Support/ConvertUTF.h"