Use -Werror in hardware/interfaces

* Remove unused local variables.

Bug: 66996870
Test: build with WITH_TIDY=1
Change-Id: I48dbbf670cc9eeff2391983788983420f8547cc9
diff --git a/nfc/1.0/default/Android.bp b/nfc/1.0/default/Android.bp
index d7f7203..3b53d16 100644
--- a/nfc/1.0/default/Android.bp
+++ b/nfc/1.0/default/Android.bp
@@ -19,6 +19,7 @@
 
 cc_binary {
     name: "android.hardware.nfc@1.0-service",
+    defaults: ["hidl_defaults"],
     relative_install_path: "hw",
     proprietary: true,
     init_rc: ["android.hardware.nfc@1.0-service.rc"],