dhcpcd: Fetch source from GitHub

pkgs/tools/networking/dhcpcd/default.nix

···
 { lib
 , stdenv
-, fetchurl
+, fetchFromGitHub
 , fetchpatch
 , pkg-config
 , udev
···
   pname = "dhcpcd";
   version = "9.4.1";
 
-  src = fetchurl {
-    url = "mirror://roy/${pname}/${pname}-${version}.tar.xz";
-    sha256 = "sha256-gZNXY07+0epc9E7AGyTT0/iFL+yLQkmSXcxWZ8VON2w=";
+  src = fetchFromGitHub {
+    owner = "NetworkConfiguration";
+    repo = "dhcpcd";
+    rev = "v${version}";
+    sha256 = "sha256-qyxON+TsAKMwAI19b5P+dT/sgxpW6m1giGcf/boFpHc=";
   };
 
   patches = [