Revert [SROA] Reuse existing lifetime markers if possible

This reverts r374692 (git commit 92694eba933ef4ea0b1b6377809ff266df37d61b)

Reproducer sent to commit thread on llvm-commits.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@374859 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed