'memslot_antagonist_args' is unused since the original
commit f73a3446 ("KVM: selftests: Add memslot modification stress
test").

Remove it.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20240602235529.228204-1-linux@treblig.orgSigned-off-by: Sean Christopherson <seanjc@google.com>