VOL-1978 - add golangci invocation and fixed issues it highlighted

Change-Id: I86f438f84e8ab7fae499a163d599b699c472afda
diff --git a/internal/pkg/commands/devicegroups.go b/internal/pkg/commands/devicegroups.go
index c499afc..7314b0a 100644
--- a/internal/pkg/commands/devicegroups.go
+++ b/internal/pkg/commands/devicegroups.go
@@ -22,6 +22,7 @@
 	"github.com/jhump/protoreflect/dynamic"
 	"github.com/opencord/voltctl/pkg/format"
 	"github.com/opencord/voltctl/pkg/model"
+	"log"
 )
 
 const (
@@ -39,8 +40,10 @@
 var deviceGroupOpts = DeviceGroupOpts{}
 
 func RegisterDeviceGroupCommands(parser *flags.Parser) {
-	parser.AddCommand("devicegroup", "device group commands", "Commands to query and manipulate VOLTHA device groups",
-		&deviceGroupOpts)
+	if _, err := parser.AddCommand("devicegroup", "device group commands", "Commands to query and manipulate VOLTHA device groups",
+		&deviceGroupOpts); err != nil {
+		log.Fatalf("Unexpected error while attempting to register device group commands : %s", err)
+	}
 }
 
 func (options *DeviceGroupList) Execute(args []string) error {