treewide: initialize empty structs with var

Change-Id: I72d3993eaf5fe57c77b1dda8218e36a8cc11813d
Reviewed-on: https://review.monogon.dev/c/monogon/+/3108
Tested-by: Jenkins CI
Reviewed-by: Serge Bazanski <serge@monogon.tech>
diff --git a/metropolis/node/core/nodeparams.go b/metropolis/node/core/nodeparams.go
index 993dd64..cb365d5 100644
--- a/metropolis/node/core/nodeparams.go
+++ b/metropolis/node/core/nodeparams.go
@@ -13,9 +13,10 @@
 	"github.com/cenkalti/backoff/v4"
 	"google.golang.org/protobuf/proto"
 
+	apb "source.monogon.dev/metropolis/proto/api"
+
 	"source.monogon.dev/metropolis/node/core/localstorage"
 	"source.monogon.dev/metropolis/pkg/supervisor"
-	apb "source.monogon.dev/metropolis/proto/api"
 )
 
 func nodeParamsFWCFG(ctx context.Context) (*apb.NodeParameters, error) {
@@ -24,7 +25,7 @@
 		return nil, fmt.Errorf("could not read firmware enrolment file: %w", err)
 	}
 
-	config := apb.NodeParameters{}
+	var config apb.NodeParameters
 	err = proto.Unmarshal(bytes, &config)
 	if err != nil {
 		return nil, fmt.Errorf("could not unmarshal: %v", err)
@@ -58,7 +59,7 @@
 	if err != nil {
 		return nil, fmt.Errorf("cannot decode base64: %w", err)
 	}
-	config := apb.NodeParameters{}
+	var config apb.NodeParameters
 	err = proto.Unmarshal(decoded, &config)
 	if err != nil {
 		return nil, fmt.Errorf("failed unmarshalling NodeParameters: %w", err)