[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
diff --git a/llvm/lib/CodeGen/InlineSpiller.cpp b/llvm/lib/CodeGen/InlineSpiller.cpp
index 3a320d9..7fb3fff 100644
--- a/llvm/lib/CodeGen/InlineSpiller.cpp
+++ b/llvm/lib/CodeGen/InlineSpiller.cpp
@@ -1145,7 +1145,7 @@
   // save a copy of LiveInterval in StackSlotToOrigLI because the original
   // LiveInterval may be cleared after all its references are spilled.
   if (StackSlotToOrigLI.find(StackSlot) == StackSlotToOrigLI.end()) {
-    auto LI = llvm::make_unique<LiveInterval>(OrigLI.reg, OrigLI.weight);
+    auto LI = std::make_unique<LiveInterval>(OrigLI.reg, OrigLI.weight);
     LI->assign(OrigLI, Allocator);
     StackSlotToOrigLI[StackSlot] = std::move(LI);
   }