nfs: return gRPC status from CephFS CreateVolume failure
nfs: return gRPC status from CephFS CreateVolume failure

The NFS Controller returns a non-gRPC error in case the CreateVolume
call for the CephFS volume fails. It is better to return the gRPC-error
that the CephFS Controller passed along.

Signed-off-by: Niels de Vos <7bda0c0ee7f47171cc808e9e60292cbc5d8140dd@redhat.com>

ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi,ceph/ceph-csi