Help msvc 2017 compiler to generate correct code
Help msvc 2017 compiler to generate correct code

This loop is wrongly vectorized by the MSVC2017 compiler, this change
is a work-around for the compiler bug.

Change-Id: Ie4c8403965c3e4cd6d70eb3dbc92148f5272f0ab
(cherry picked from commit 5b33d7184bf319d9c10e34ef0fdcdd244d2fdb56)

GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom