Re: graphics/png: update to 1.6.40

[Christian Weisgerber]

Klemens Nanni:

> >From june 2023:
> http://www.libpng.org/pub/png/src/libpng-1.6.40-README.txt

ok naddy@

-- 
Christian "naddy" Weisgerber                          na...@mips.inka.de