[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/ObjectYAML/ELFEmitter.cpp b/llvm/lib/ObjectYAML/ELFEmitter.cpp
index d2ceb40..5e53baf 100644
--- a/llvm/lib/ObjectYAML/ELFEmitter.cpp
+++ b/llvm/lib/ObjectYAML/ELFEmitter.cpp
@@ -188,7 +188,7 @@
   if (Doc.Sections.empty() || Doc.Sections.front()->Type != ELF::SHT_NULL)
     Doc.Sections.insert(
         Doc.Sections.begin(),
-        llvm::make_unique<ELFYAML::Section>(
+        std::make_unique<ELFYAML::Section>(
             ELFYAML::Section::SectionKind::RawContent, /*IsImplicit=*/true));
 
   std::vector<StringRef> ImplicitSections = {".symtab", ".strtab", ".shstrtab"};
@@ -201,7 +201,7 @@
     if (DocSections.count(SecName))
       continue;
 
-    std::unique_ptr<ELFYAML::Section> Sec = llvm::make_unique<ELFYAML::Section>(
+    std::unique_ptr<ELFYAML::Section> Sec = std::make_unique<ELFYAML::Section>(
         ELFYAML::Section::SectionKind::RawContent, true /*IsImplicit*/);
     Sec->Name = SecName;
     Doc.Sections.push_back(std::move(Sec));