[clang] [flang] [llvm] [IR] Remove size argument from lifetime intrinsics (PR #150248)

[Eli Friedman via llvm-commits]

efriedma-quic wrote:

Probably should release note, yes.

Also, can we try to land some of the changes separately?  I mean, some things can't land separately, or it would be a pain in the neck to land them separately because of test changes, but we can at least merge the SelectionDAG bits and the analysis changes first, so the remaining bits are easier to review.

https://github.com/llvm/llvm-project/pull/150248