x86: sbrdsp: Implement SSE sum64x5

698 to 174 cycles on Arrandale. Unrolling is a 6 cycles gain.

Signed-off-by: Diego Biurrun <diego@biurrun.de>
x86: sbrdsp: Implement SSE qmf_post_shuffle

255 to 174 cycles on Arrandale / Win64. Unrolling yields no gain.

Signed-off-by: Diego Biurrun <diego@biurrun.de>