Revert "Emit lifetime.start / lifetime.end markers for unnamed temporary objects."

This reverts commit dbf785a6432f78a8ec229665876647c4cc610d3d, while I qm
investigating a buildbot failure.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@213380 91177308-0d34-0410-b5e6-96231b3b80d8