Fix a case in SROA where lifetime intrinsics could inhibit alloca promotion. In

Fix a case in SROA where lifetime intrinsics could inhibit alloca promotion.  In
this case, the code path dealing with vector promotion was missing the explicit
checks for lifetime intrinsics that were present on the corresponding integer
promotion path.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215148 91177308-0d34-0410-b5e6-96231b3b80d8