ima-evm-utils: add nickcao to maintainers

pkgs/os-specific/linux/ima-evm-utils/default.nix

···
     homepage = "https://sourceforge.net/projects/linux-ima/";
     license = lib.licenses.gpl2;
     platforms = lib.platforms.linux;
-    maintainers = with lib.maintainers; [ ];
+    maintainers = with lib.maintainers; [ nickcao ];
   };
 }