row_neon64 fix for warning on ios where int width doesnt match %2 size which is 64 bit by default.  change size to explicitely 32 bit with %w2. BUG=437 TESTED=try bots R=bcornell@google.com
row_neon64 fix for warning on ios where int width doesnt match %2 size which is 64 bit by default.  change size to explicitely 32 bit with %w2.
BUG=437
TESTED=try bots
R=bcornell@google.com

Review URL: https://webrtc-codereview.appspot.com/47119004

git-svn-id: a51711482b6ba0e1d1ab095578a045eeae45ac9a@1399 16f28f9a-4ce2-e073-06de-1de4eb20be90

rig-project/libyuv,rig-project/libyuv,rig-project/libyuv