Stir together flour, oats, brown sugar, baking powder, cinnamon, cloves, and salt in a large bowl. In a separate large bowl, lightly beat together the milk, egg, pumpkin, and oil. Stir flour mixture into the pumpkin mixture, blending just until moistened. Heat a lightly greased griddle over medium high heat. Pour batter, 1/3 cup at a time, onto the prepared griddle. Make a jack-o-lantern face in each pancake with the chocolate chips. Cook until bubbles appear on the surface, then flip and cook until golden brown on the other side, about 5 minutes per side.