executor: increase coverage size from 16K to 64K PCs
executor: increase coverage size from 16K to 64K PCs

On some KVM syscalls soverage reaches 36K+ PCs.

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