By Nicholas Riccardi, Times Staff Writer FT. CARSON, Colo. -- A military jury late Saturday night convicted an Army interrogator of negligent homicide in the death an Iraqi general who had been stuffed face-first in a sleeping bag. After seven hours of deliberations the six-member military panel opted not to convict Chief Warrant Officer Lewis E. Welshofer Jr. of murder, which would have carried a life sentence. Instead, the panel ruled that the death was a negligent homicide, a finding that caries a maximum three-year term in a military prison. The panel also found Welshofer guilty of dereliction of duty....