Fix SSE plog<float> to return -INF on 0
(transplanted from fc72171c7e9e2fcc574565d3f579e96b46d59221)

--HG--
branch : 3.1
extra : transplant_source : %FCr%17%1C%7E%9E/%CCWEe%D3%F5y%E9kF%D5%92%21