chore(hd-idle): fix fatrace warning

hosts/odin/system/hd-idle.nix

@@ -10,6 +10,8 @@ let
     lib.concatStringsSep " " (lib.map (disk: "-a ${disk} -i 600") disks);
 
   args = mkArgString disks;
+  fatrace = lib.getExe' pkgs.fatrace "fatrace";
+  hd-idle = lib.getExe' pkgs.hd-idle "hd-idle";
 in
 {
   environment.systemPackages = [ pkgs.hd-idle pkgs.fatrace ];
@@ -26,7 +28,7 @@ in
 
     serviceConfig = {
       Type = "simple";
-      ExecStart = "${lib.getExe pkgs.hd-idle} ${args}";
+      ExecStart = "${hd-idle} ${args}";
       Restart = "always";
     };
   };
@@ -37,7 +39,7 @@ in
     wants = [ "local-fs.target" ];
 
     serviceConfig = {
-      ExecStart = "${lib.getExe pkgs.fatrace} --timestamp /mnt/storage";
+      ExecStart = "${fatrace} --timestamp /mnt/storage";
       Restart = "always";
       User = "root";
     };