libnsgif: move to by-name

pkgs/applications/networking/browsers/netsurf/default.nix

···
     libhubbub = pkgs.libhubbub;
     libnsbmp = pkgs.libnsbmp;
     libnsfb = pkgs.libnsfb;
-    libnsgif = callPackage ./libnsgif.nix { };
+    libnsgif = pkgs.libnsgif;
     libnslog = callPackage ./libnslog.nix { };
     libnspsl = callPackage ./libnspsl.nix { };
     libnsutils = callPackage ./libnsutils.nix { };

pkgs/applications/networking/browsers/netsurf/libnsgif.nix pkgs/by-name/li/libnsgif/package.nix

···
   fetchurl,
   pkg-config,
   buildPackages,
-  buildsystem,
+  netsurf-buildsystem,
 }:
 
 stdenv.mkDerivation (finalAttrs: {
-  pname = "netsurf-libnsgif";
+  pname = "libnsgif";
   version = "1.0.0";
 
   src = fetchurl {
···
 
   nativeBuildInputs = [ pkg-config ];
 
-  buildInputs = [ buildsystem ];
+  buildInputs = [ netsurf-buildsystem ];
 
   makeFlags = [
     "PREFIX=$(out)"
-    "NSSHARED=${buildsystem}/share/netsurf-buildsystem"
+    "NSSHARED=${netsurf-buildsystem}/share/netsurf-buildsystem"
     "BUILD_CC=$(CC_FOR_BUILD)"
   ];
 
···
     homepage = "https://www.netsurf-browser.org/projects/libnsgif/";
     description = "GIF Decoder for netsurf browser";
     license = lib.licenses.mit;
-    inherit (buildsystem.meta) maintainers platforms;
+    inherit (netsurf-buildsystem.meta) maintainers platforms;
   };
 })