Re-land "[compiler-rt] Migrate llvm::make_unique to std::make_unique"

With the compiler-rt check for C++14 updated in r368960, this should now
be fine to land.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@369009 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed