passpoint-r2: add trust anchors for WFA Passpoint Release 2.

It is required to authenticate OSU server with OSU Server certificate
singed with one of WFA trust anchors.

Bug: 112052266
Test: live test with Passpoint r2 AP
Change-Id: I01f498c875b067edd03a8bc008644281cb4ab1ff
Signed-off-by: Ecco Park <eccopark@google.com>

packages/OsuLogin/AndroidManifest.xml

@@ -23,6 +23,7 @@
     <uses-permission android:name="android.permission.INTERNET" />
 
     <application
+        android:networkSecurityConfig="@xml/network_security_config"
         android:enabled="true"
         android:label="@string/app_name"
         android:configChanges="keyboardHidden|orientation|screenSize"

packages/OsuLogin/res/xml/network_security_config.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<network-security-config>
+<base-config cleartextTrafficPermitted="true">
+    <trust-anchors>
+        <certificates src="system" />
+        <certificates src="wfa" />
+    </trust-anchors>
+</base-config>
+</network-security-config>