syslinux: Drop samueldr as maintainer

pkgs/os-specific/linux/syslinux/default.nix

···
     homepage = "https://www.syslinux.org/";
     description = "Lightweight bootloader";
     license = licenses.gpl2Plus;
-    maintainers = [ maintainers.samueldr ];
+    maintainers = [ ];
     platforms = [ "i686-linux" "x86_64-linux" ];
   };
 }