[llvm] Migrate llvm::make_unique to std::make_unique

Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.

llvm-svn: 369013

llvm/lib/Object/WasmObjectFile.cpp

@@ -56,7 +56,7 @@ LLVM_DUMP_METHOD void WasmSymbol::dump() const { print(dbgs()); }
 Expected<std::unique_ptr<WasmObjectFile>>
 ObjectFile::createWasmObjectFile(MemoryBufferRef Buffer) {
   Error Err = Error::success();
-  auto ObjectFile = llvm::make_unique<WasmObjectFile>(Buffer, Err);
+  auto ObjectFile = std::make_unique<WasmObjectFile>(Buffer, Err);
   if (Err)
     return std::move(Err);