client/simplestreams_images.go
func (r *ProtocolSimpleStreams) GetPrivateImageFile(fingerprint string, secret string, req ImageFileRequest) (*ImageFileResponse, error) {
	return nil, fmt.Errorf("Private images aren't supported by the simplestreams protocol")
}
func (r *ProtocolSimpleStreams) GetPrivateImageFile(fingerprint string, secret string, req ImageFileRequest) (*ImageFileResponse, error) {
	return nil, fmt.Errorf("Private images aren't supported by the simplestreams protocol")
}
// GetPrivateImageFile isn't relevant for the simplestreams protocol