pkg/repro: fix nil target in prog
pkg/repro: fix nil target in prog

google/syzkaller,google/syzkaller,xairy/syzkaller,google/syzkaller,zoulasc/syzkaller,dotweiba/syzkaller,google/syzkaller,xairy/syzkaller,xairy/syzkaller,google/syzkaller,zoulasc/syzkaller,dotweiba/syzkaller,dotweiba/syzkaller,xairy/syzkaller,zoulasc/syzkaller,dotweiba/syzkaller,google/syzkaller,google/syzkaller,xairy/syzkaller,zoulasc/syzkaller,xairy/syzkaller,xairy/syzkaller