[llvm] [SDAG] Harden assumption in getMemsetStringVal (PR #126207)

[Cullen Rhodes via llvm-commits]

c-rhodes wrote:

> Could have kept the constant fp case, I guess. Also could unconditionally go through the bitcast

Thanks for review. By unconditionally go through the bitcast, do you mean remove the int case? 


https://github.com/llvm/llvm-project/pull/126207