nir: Rename replicated-result dot-product instructions

All these instructions replicate the result of a N-component dot-product to a vec4. Naming them fdot_replicatedN gives the impression that are some sort of abstract dot-product that replicates the result to a vecN. They also deviate from fdph_replicated... which nobody would reasonably consider naming fdot_replicatedh.

Naming these opcodes fdotN_replicated more closely matches what they are, and it matches the pattern of fdph_replicated.

I believe that the only reason these opcodes were named this way was because it simplified the implementation of the binop_reduce function in nir_opcodes.py. I made some fairly simple changes to that function, and I think the end result is ok.

The bulk of the changes come from the sed rename:

    sed --in-place -e 's/fdot_replicated\([234]\)/fdot\1_replicated/g' \
        $(grep -r 'fdot_replicated[234]' src/)