syz-gce: allow to specify enabled/disabled syscalls
syz-gce: allow to specify enabled/disabled syscalls

dotweiba/syzkaller,google/syzkaller,zoulasc/syzkaller,xairy/syzkaller,xairy/syzkaller,google/syzkaller,hyz0906/syzkaller,zoulasc/syzkaller,zoulasc/syzkaller,xairy/syzkaller,google/syzkaller,hyz0906/syzkaller,xairy/syzkaller,hyz0906/syzkaller,google/syzkaller,google/syzkaller,google/syzkaller,google/syzkaller,hyz0906/syzkaller,xairy/syzkaller,xairy/syzkaller,hyz0906/syzkaller,zoulasc/syzkaller,dotweiba/syzkaller,xairy/syzkaller,dotweiba/syzkaller,dotweiba/syzkaller