fix: assign value of multicast setting properly

Fix https://github.com/siderolabs/talos/pull/12233/files#r2564186653

Signed-off-by: Mateusz Urbanek <mateusz.urbanek@siderolabs.com>
(cherry picked from commit 7f7079f)

Author: shanduur

internal/app/machined/pkg/controllers/network/link_config.go

@@ -17,6 +17,7 @@ import (
 	"github.com/siderolabs/gen/optional"
 	"github.com/siderolabs/gen/pair/ordered"
 	"github.com/siderolabs/gen/xslices"
+	"github.com/siderolabs/go-pointer"
 	"github.com/siderolabs/go-procfs/procfs"
 	"go.uber.org/zap"
 
@@ -440,8 +441,7 @@ func (ctrl *LinkConfigController) processLinkConfigs(logger *zap.Logger, linkMap
 		}
 
 		if multicast, ok := linkConfig.Multicast().Get(); ok {
-			linkMap[linkName].Multicast = new(bool)
-			*linkMap[linkName].Multicast = multicast
+			linkMap[linkName].Multicast = pointer.To(multicast)
 		}
 
 		switch specificLinkConfig := linkConfig.(type) {

internal/app/machined/pkg/controllers/network/link_spec_test.go

@@ -19,6 +19,7 @@ import (
 	"github.com/cosi-project/runtime/pkg/safe"
 	"github.com/jsimonetti/rtnetlink/v2"
 	"github.com/siderolabs/gen/xslices"
+	"github.com/siderolabs/go-pointer"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/stretchr/testify/suite"
@@ -102,8 +103,7 @@ func (suite *LinkSpecSuite) TestDummy() {
 
 	// attempt to change multicast flag
 	ctest.UpdateWithConflicts(suite, dummy, func(r *network.LinkSpec) error {
-		r.TypedSpec().Multicast = new(bool)
-		*r.TypedSpec().Multicast = true
+		r.TypedSpec().Multicast = pointer.To(true)
 
 		return nil
 	})
@@ -115,7 +115,7 @@ func (suite *LinkSpecSuite) TestDummy() {
 	// attempt to disable multicast
 	ctest.UpdateWithConflicts(suite, dummy, func(r *network.LinkSpec) error {
 		r.TypedSpec().Multicast = new(bool)
-		*r.TypedSpec().Multicast = false
+		r.TypedSpec().Multicast = pointer.To(false)
 
 		return nil
 	})