KVM: Disable manual dirty log when dirty ring enabled

KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is for KVM_CLEAR_DIRTY_LOG, which is only
useful for KVM_GET_DIRTY_LOG.  Skip enabling it for kvm dirty ring.

More importantly, KVM_DIRTY_LOG_INITIALLY_SET will not wr-protect all the pages
initially, which is against how kvm dirty ring is used - there's no way for kvm
dirty ring to re-protect a page before it's notified as being written first
with a GFN entry in the ring!  So when KVM_DIRTY_LOG_INITIALLY_SET is enabled
with dirty ring, we'll see silent data loss after migration.

Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210506160549.130416-10-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>