[llvm] [DAG] Retain original alignment in bitcast(load(x)) -> load(x) fold (PR #75922)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

It looked like your patch was going to get bogged down into ISD::LOAD vs ISD;;ATOMIC_LOAD - but if its sorted then this can be abandoned

https://github.com/llvm/llvm-project/pull/75922