[llvm] [NVPTX] support immediate values in st.param instructions (PR #91523)

[Artem Belevich via llvm-commits]

https://github.com/Artem-B commented:

Just curious -- do we expect to see any benefits from this in SASS?
ptxas usally deals with `mov const->register; op(register)`  just fine and with parameters living mostly in registers, the notion of vectorized loads/stores in parameter space is largely a fiction.

What does this change buy us, other than a few less register moves on PTX level?

https://github.com/llvm/llvm-project/pull/91523