Support multiple displays in fingerprint VHAL

Bug: 348076336
Test: atest android.hardware.biometrics.fingerprint.* -c
Test: atest BiometricsE2eTests:BiometricPromptAuthSuccessTest
Change-Id: Ia0e26e41b951cf00d8d098983a05f3916b12af5c
diff --git a/biometrics/fingerprint/aidl/default/include/FakeFingerprintEngineRear.h b/biometrics/fingerprint/aidl/default/include/FakeFingerprintEngineRear.h
index 14d5399..12091ee 100644
--- a/biometrics/fingerprint/aidl/default/include/FakeFingerprintEngineRear.h
+++ b/biometrics/fingerprint/aidl/default/include/FakeFingerprintEngineRear.h
@@ -23,6 +23,8 @@
 
 // A fake engine that is backed by system properties instead of hardware.
 class FakeFingerprintEngineRear : public FakeFingerprintEngine {
+    static SensorLocation defaultSensorLocation[];
+
   public:
     FakeFingerprintEngineRear() : FakeFingerprintEngine() {}
     ~FakeFingerprintEngineRear() {}