Lint: InspectImage varlink api should return errors that occurred

Not just nil.

Addressing:
pkg/varlinkapi/images.go:273:15⚠️ ineffectual assignment to err (ineffassign)

Signed-off-by: Šimon Lukašík <slukasik@redhat.com>

pkg/varlinkapi/images.go

@@ -271,6 +271,9 @@ func (i *LibpodAPI) InspectImage(call iopodman.VarlinkCall, name string) error {
 		return call.ReplyImageNotFound(name)
 	}
 	inspectInfo, err := newImage.Inspect(getContext())
+	if err != nil {
+		return call.ReplyErrorOccurred(err.Error())
+	}
 	b, err := json.Marshal(inspectInfo)
 	if err != nil {
 		return call.ReplyErrorOccurred(fmt.Sprintf("unable to serialize"))