[llvm] [SDAG] Add missing float type legalizations for FMODF (PR #128055)

[Benjamin Maxwell via llvm-commits]

MacDue wrote:

> There should be no CHAIN_BARRIER machineinstrs. This is missing necessary support code for it, but it should not be necessary. 

Ah right :+1: I've updated `Select_CHAIN_BARRIER` to simply remove the `CHAIN_BARRIER` node.  



https://github.com/llvm/llvm-project/pull/128055