OpenStack instance creation errors aren't logged

[macaptain]

/kind bug

What steps did you take and what happened:

If OpenStack instance creation fails, the error is logged as: error creating Openstack instance: <nil>

E0601 10:13:01.337910       8 openstackmachine_controller.go:389] controller-runtime/manager/controller/openstackmachine "msg"="OpenStack instance cannot be created: error creating Openstack instance: error creating Openstack instance: <nil>" "error"="UpdateError" "cluster"="basic-1" "machine"="basic-1-control-plane-v844x" "name"="basic-1-control-plane-bv6dz" "namespace"="default" "openStackCluster"="basic-1" "openStackMachine"="basic-1-control-plane-bv6dz" "reconciler group"="infrastructure.cluster.x-k8s.io" "reconciler kind"="OpenStackMachine" 

This is because the error from server creation is reassigned to be the error from ports deletion before the error is logged:

cluster-api-provider-openstack/pkg/cloud/services/compute/instance.go

Lines 230 to 235 in 04e0b54

	if mc.ObserveRequest(err) != nil {
	if err = s.deletePorts(eventObject, portList); err != nil {
	return nil, err
	}
	return nil, fmt.Errorf("error creating Openstack instance: %v", err)
	}

What did you expect to happen:
I expect to see the error from the OpenStack response included in the controller logs.

Environment:

• Cluster API Provider OpenStack version (Or git rev-parse HEAD if manually built):
• Cluster-API version:
• OpenStack version:
• Minikube/KIND version:
• Kubernetes version (use kubectl version):
• OS (e.g. from /etc/os-release):

[jichenjc]

good catch

do you mind create a PR to fix ? should be relatively not that hard...