nir: Split nir_lower_subgroup_options::lower_vote_eq into two bits

On NVIDIA, we can do a vote_ieq on bool in one hardware op so we don't
want that lowered.  We do want to lower vote_feq and other vote_ieq,
though.

Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25894>
5 files changed