I heard someone say チョンボを犯した in a situation where they could not possibly be talking about 麻雀. I don't know if he plays 麻雀 or not, but it made me wonder, how common is using チョンボ to mean mistake among people who don't play 麻雀?
Yes, チョンボ can be used in non-mahjong situations. As you know, it is originally a mahjong term, but its meaning of "making a mistake" has been carried over to everyday usage. It is even in dictionaries.
As for how common, I don't hear it all too often, but enough for me not to automatically assume it's about mahjong just by hearing it.
Note that there are many mahjong terms that have made it into everyday use. テンパる、メンツ、リーチ、安牌、ワンチャン are ones I still hear used a lot.