Set CPPFLAGS, add more recipes

recipes/libpng/recipe.toml

recipes/libvorbis/recipe.toml

recipes/logd/recipe.toml

recipes/nasm/recipe.toml

recipes/netstack/recipe.toml

recipes/netutils/recipe.toml

recipes/nulld/recipe.toml

recipes/pkgar/recipe.toml

recipes/pkgutils/recipe.toml

recipes/ptyd/recipe.toml

recipes/ramfs/recipe.toml

recipes/redoxerd/recipe.toml

recipes/redoxfs/recipe.toml

recipes/sed/recipe.toml

recipes/shellstorm/recipe.toml

recipes/smith/recipe.toml

recipes/zerod/recipe.toml

src/bin/cook.rs