Apparently he has yet to decide which charity he will donate his paycheque to. You’d think a big philanthropist like Trump would already have a favourite charity in mind to give it to. /sarcasm
Seriously though, even probably planned to give it to his own foundation before it got into trouble for all irregularities.
My money is on him waffling about it for as long as he can while collecting interest on it, before donating a token amount, pocketing the rest and declaring how awesome he is.