Support: make floating-exception header private

It has only one user. This eliminates the last include of
config.h from the public headers -- ideally, config.h
shouldn't even be installed by `make install` anymore.

llvm-svn: 133713

llvm/lib/Analysis/ConstantFolding.cpp

@@ -31,9 +31,10 @@
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/GetElementPtrTypeIterator.h"
 #include "llvm/Support/MathExtras.h"
-#include "llvm/Support/FEnv.h"
 #include <cerrno>
 #include <cmath>
+
+#include "FEnv.h"
 using namespace llvm;
 
 //===----------------------------------------------------------------------===//

llvm/lib/Analysis/FEnv.h

@@ -1,4 +1,4 @@
-//===- llvm/Support/FEnv.h - Host floating-point exceptions ------*- C++ -*-===//
+//===- FEnv.h - Host floating-point exceptions ------------------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //