Revert of Optimize RGB16 blitH functions with NEON for ARM platform. (patchset #2...

Revert of Optimize RGB16 blitH functions with NEON for ARM platform. (patchset #2 id:20001 of https://codereview.chromium.org/1229673008/)

Reason for revert:
This doesn't draw correctly, e.g. our GM test named dashcubics.

Good: https://gold.skia.org/img/images/0f7e8e226379afbad8a700e0a80fd8f1.png

Bad:
https://gold.skia.org/img/images/56ce15fc67436065a3db4b8ee31f13ae.png

Original issue's description:
> Optimize RGB16 blitH functions with NEON for ARM platform.
>
> Here are some performance resultsi on Nexus 9:
> SkRGB16BlitterBlitH_neon:
>     +--------+-----------+
>     |height  |  C/NEON   |
>     +--------+-----------+
>     |1       | 0.888531  |
>     +--------+-----------+
>     |8       | 1.231800  |
>     +--------+-----------+
>     |18      | 1.073327  |
>     +--------+-----------+
>     |32      | 1.136991  |
>     +--------+-----------+
>     |76      | 1.174638  |
>     +--------+-----------+
>     |85      | 1.188551  |
>     +--------+-----------+
>     |120     | 1.180261  |
>     +--------+-----------+
>     |128     | 1.183726  |
>     +--------+-----------+
>     |512     | 1.220806  |
>     +--------+-----------+
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/6c72d5740231f47c664a8e765a8df05cd124c88c

TBR=djsollen@google.com,caryclark@google.com,reed@google.com,bero@linaro.com,yang.zhang@linaro.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1268513003