MSNBC’s Mika Brzezinski warned that Donald Trump made clear in a Fox News interview that he’s completely serious about prosecuting his enemies if he returns to the White House. The former president sat down with conservative broadcaster Sean Hannity, who lobbed softball questions that gave Trump an opportunity to walk back those threats against president Joe Biden and others, but Trump instead doubled down and claimed he would be justified in using the criminal justice system to seek retribution. “Help me out here – first of all, no criminality,” Brzezinski said, addressing one of Trump’s clai…