That's not too bad. That will most likely clean right up. Scrape it off first, then go back over it lots of times with alcohol-soaked Q-tips until they stop turning brown. Then you know you got basically all of it off of there.

It's somewhat important not to turn it on at least for very long until you clean it pretty well.

It doesn't look bad to me. I had one way worse than this (a 6100) and just scrubbing with Q-tips like that did the trick. Battery goop had also gotten into several small surface-mounted chips like that and they turned out fine.