How can I disable the front status LED when charging my device?
I haven't seem any such options or settings for any device so far. You can try these apps


LightFlow Lite
Adjbrightness


but I doubt these would work properly. (I can't check as my device doesn't have LED notification light.)

I believe this kind of things are only doable via Custom ROMs. You would have to check your device development forums. Start here - Huwaei U8860 - xda-developers.

I don't think you can get an universal solution. If there has been a way to do it via Android APIs it would already be in Settings I believe.