Fix clang-rocm-6.4.0 build (#88)

The patch is cherrypick of LLVM commit b0baa1d8

Author: yxsamliu

build/patches/ce-clang-rocm-6.4.0.patch

@@ -0,0 +1,18 @@
+diff --git a/llvm/tools/gold/gold-plugin.cpp b/llvm/tools/gold/gold-plugin.cpp
+index 0d4ca5299689..1a9ecffae38c 100644
+--- a/llvm/tools/gold/gold-plugin.cpp
++++ b/llvm/tools/gold/gold-plugin.cpp
+@@ -1099,10 +1099,10 @@ static std::vector<std::pair<SmallString<128>, bool>> runLTO() {
+         std::make_unique<llvm::raw_fd_ostream>(FD, true));
+   };
+ 
+-  auto AddBuffer = [&](size_t Task, const Twine &moduleName,
++  auto AddBuffer = [&](size_t Task, const Twine &ModuleName,
+                        std::unique_ptr<MemoryBuffer> MB) {
+-    auto Stream = *AddStream(Task, ModuleName);
+-    Stream->OS << MB->getBuffer();
++    auto Stream = AddStream(Task, ModuleName);
++    *Stream->OS << MB->getBuffer();
+     check(Stream->commit(), "Failed to commit cache");
+   };
+