Fix proguard rules for Struct in NetworkStack am: 9a82bbf368

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/1674688

Change-Id: I49cf42126e03c4fd449577bd1167dd74dec1b6a5
diff --git a/Tethering/proguard.flags b/Tethering/proguard.flags
index 9ab56c2..75ecdce 100644
--- a/Tethering/proguard.flags
+++ b/Tethering/proguard.flags
@@ -9,7 +9,7 @@
 }
 
 -keepclassmembers public class * extends com.android.networkstack.tethering.util.Struct {
-    public <init>(...);
+    *;
 }
 
 -keepclassmembers class android.net.ip.IpServer {