SSSE3 optimized 10 bit YUV conversion to ARGB in single step.

Bug: libyuv:751
Test:  I010ToARGB
Change-Id: I234b2850e35992113ee6bd638732bafc7010a60d
Reviewed-on: https://chromium-review.googlesource.com/848238
Commit-Queue: Frank Barchard <fbarchard@chromium.org>
Reviewed-by: Frank Barchard <fbarchard@chromium.org>
Reviewed-by: richard winterton <rrwinterton@gmail.com>