[owners] Add OWNERs files to libpng

Bug: 77802
Change-Id: I4f77a0da2f7754e72a41af24ec40c588441d1439
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/libpng/+/536927
Reviewed-by: Daniel Salazar Villarreal <villarreald@google.com>
1 file changed