Switch back to upstream libpng-sys

Author: lilith

Cargo.lock

@@ -27,7 +27,7 @@ opt-level = 2
 
 [patch.crates-io]
 #  libwebp-sys = { git = "https://github.com/imazen/libwebp-sys" }
-libpng-sys = { git = "https://github.com/lilith/rust-libpng-sys" }
+libpng-sys = { git = "https://github.com/kornelski/rust-libpng-sys" }
 rgb.git = "https://github.com/kornelski/rust-rgb"
 load_image.git = "https://gitlab.com/lilith6/load_image.git"