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

[Benjamin Maxwell via llvm-commits]

MacDue wrote:

Now that I've removed the CHAIN_BARRIER MIs using the new CHAIN_BARRIER opcode does not change any tests that previously depended on updating the root, which is nice. 

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