roll libpng to pre-1.6.38

This rolls in the patch to fix NEON + clang-cl.

Cq-Include-Trybots: skia.primary:Build-Win-Clang-arm64-Release
Change-Id: Id34730763ff56b89bb49033001ffb42b09d55a61
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/210360
Commit-Queue: Mike Klein <mtklein@google.com>
Commit-Queue: Leon Scroggins <scroggo@google.com>
Auto-Submit: Mike Klein <mtklein@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>
2 files changed