Add @UnsupportedAppUsage annotations

For packages:
  android.nfc.tech
  android.nfc.dta
  android.nfc.cardemulation
  android.nfc

This is an automatically generated CL. See go/UnsupportedAppUsage
for more details.

Exempted-From-Owner-Approval: Mechanical changes to the codebase
which have been approved by Android API council and announced on
android-eng@

Bug: 110868826
Test: m
Merged-In: I6176e760bb0912fd075a36d65fa0b49680c14aa3
Change-Id: I2da62ff82b75ba4a5a0a64d02c6ebdb101992765
diff --git a/core/java/android/nfc/NfcActivityManager.java b/core/java/android/nfc/NfcActivityManager.java
index c7d4c65..87e644f 100644
--- a/core/java/android/nfc/NfcActivityManager.java
+++ b/core/java/android/nfc/NfcActivityManager.java
@@ -16,6 +16,7 @@
 
 package android.nfc;
 
+import android.annotation.UnsupportedAppUsage;
 import android.app.Activity;
 import android.app.Application;
 import android.content.ContentProvider;
@@ -45,6 +46,7 @@
     static final String TAG = NfcAdapter.TAG;
     static final Boolean DBG = false;
 
+    @UnsupportedAppUsage
     final NfcAdapter mAdapter;
 
     // All objects in the lists are protected by this