Maint: move misplaced writeOpenvpnConf in openvpn

internal/openvpn/config.go

@@ -0,0 +1,18 @@
+package openvpn
+
+import (
+	"os"
+	"strings"
+)
+
+func (l *Loop) writeOpenvpnConf(lines []string) error {
+	file, err := os.OpenFile(l.targetConfPath, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0644)
+	if err != nil {
+		return err
+	}
+	_, err = file.WriteString(strings.Join(lines, "\n"))
+	if err != nil {
+		return err
+	}
+	return file.Close()
+}