NEW YORK — Pope Francis’ call Wednesday for a church of “open doors” that welcomes divorced Catholics prompted speculation over whether he was signaling support for easing the ban on Communion for couples who remarry without a church annulment. The issue is at the center of an extraordinarily public debate among cardinals from around the world who will gather this October at the Vatican for a synod, or meeting, on the family, where treatment of such couples will be a key topic. “He wants the church to get over a psychology that if you’re divorced and remarried that you’re a lesser Catholic,” said Phillip Thompson, executive director of the Aquinas Center of Theology at Emory University in Atlanta.