YUY2ToI422_Any_Neon previously required 16 pixels and duplicated
the last pixel.  The replication was not necessary after a previous
change to treat YUY2 to 4 byte macro pixels.

TBR=harryjin@google.com
BUG=libyuv:648
TESTED=util/android/test_runner.py gtest -s libyuv_unittest -t 7200 --verbose --release --gtest_filter=*YUY2ToI422* -a "--libyuv_width=17 --libyuv_height=7 --libyuv_repeat=999 --libyuv_flags=1"

Review URL: https://codereview.chromium.org/2399143002 .