<limits.h> includes <linux/limits.h> on Linux, no need to special-case it

llvm-svn: 173578
diff --git a/clang/lib/Basic/FileManager.cpp b/clang/lib/Basic/FileManager.cpp
index 19f170e..9cc5902 100644
--- a/clang/lib/Basic/FileManager.cpp
+++ b/clang/lib/Basic/FileManager.cpp
@@ -41,9 +41,7 @@
 #endif
 #endif
 #if defined(LLVM_ON_UNIX)
-#if defined(__linux__)
-#include <linux/limits.h>
-#endif
+#include <limits.h>
 #endif
 using namespace clang;