overlay: Limit max fingerprints to 4 per user

Trying to add more than 4 fingerprints per user causes the Udfps
overlay to not appear and shows the following message in logs:
`E Biometrics/EnrollClient: Reached enrollment limit`.

Change-Id: I26707d5b50b28d032b117e22ba703c5fc0dfe3a2

overlay-lineage/frameworks/base/core/res/res/values/config.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright 2021 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+
+<resources>
+    <integer name="config_fingerprintMaxTemplatesPerUser">4</integer>
+</resources>