nir: Mark negative re-distribution on fadd as imprecise
Otherwise, it would mutate fneg(fadd(-0, 0))
into fadd(0, -0)
which
isn't correct since -0 + (+0) = +0 + (-0) = +0.
This fixes the OpenCL contraction tests on Iris.
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Otherwise, it would mutate fneg(fadd(-0, 0))
into fadd(0, -0)
which
isn't correct since -0 + (+0) = +0 + (-0) = +0.
This fixes the OpenCL contraction tests on Iris.