Freezer burn chicken is not bad to eat.
Freezer burn does not affect the safety of the chicken or other meat that it happens too.
When meat loses the moisture when it's being frozen then the meat gets freezer burn.
The Freezer burn makes the chicken or other meat less appealing to eat and the freezer burn meat will not be as good to eat.
However freezer burn meat is 100 percent safe to eat.
I've eaten freezer burn chicken several times as well as other freezer burned meats and never have gotten sick.
If you don't like the taste of freezer burned meat you can use the freezer burned meat in soups, stews etc where you will not notice the taste of the freezer burned meat.