pkgs/iotools: Support only x86-based Linux platforms

Support only x86-based Linux platforms since everything else is
untested.

Signed-off-by: Felix Singer <[e-mail]>

pkgs/tools/misc/iotools/default.nix

···
     homepage = "https://github.com/adurbin/iotools";
     license = licenses.gpl2Only;
     maintainers = with maintainers; [ felixsinger ];
-    platforms = platforms.linux;
+    platforms = [ "x86_64-linux" "i686-linux" ];
   };
 }