aco: consider affinities when creating v_mac_f32

aco: consider affinities when creating v_mac_f32

Totals from 8487 (6.65% of 127638) affected shaders:
CodeSize: 62061988 -> 62058020 (-0.01%); split: -0.01%, +0.01%
Instrs: 11910757 -> 11885409 (-0.21%); split: -0.21%, +0.00%
Copies: 1065244 -> 1040945 (-2.28%); split: -2.30%, +0.02%
Branches: 349665 -> 348914 (-0.21%)

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4990>