The state Medical Examining Board on Tuesday dropped all charges against a former Fairfield doctor who illegally prescribed oxycodone because the doctor has voluntarily surrendered his medical license. Paul Bellofiore, 57, of Trumbull, gave up his license in October, state Department of Public Health records show. Bellofiore, who had practiced in Fairfield, also agreed not to contest the allegations against him if he ever seeks to have his license reinstated. In February, Bellofiore was sentenced in U.S. District Court in Hartford to two years of probation for illegally prescribing the painkiller. Judge Alvin W. Thompson also ordered him to perform 200 hours of community service and prohibited Bellofiore from writing prescriptions for controlled substances until Oct.