nir/algebraic: mark some optimizations with fsat(NaN) as inexact

nir/algebraic: mark some optimizations with fsat(NaN) as inexact

If a is Nan, fsat(NaN) is expected to be 0 and some optimizations
should be marked as inexact.

Fixes a GPU hang with Death Stranding and RADV/ACO (RADV/LLVM
isn't affected because it lowers fsat).

No fossils-db change.

Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/3368
Cc: mesa-stable
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6519>