Add triggerImsDeregistration to IRadioImsIndication

Bug: 216387835
Test: build & flash
Change-Id: I1ef313c993816ee86233cdc5f17380ed157c38ee
diff --git a/radio/aidl/vts/radio_ims_utils.h b/radio/aidl/vts/radio_ims_utils.h
index 61e4254..541077f 100644
--- a/radio/aidl/vts/radio_ims_utils.h
+++ b/radio/aidl/vts/radio_ims_utils.h
@@ -67,6 +67,8 @@
 
     virtual ndk::ScopedAStatus notifyAnbr(RadioIndicationType type, int qosSessionId,
             ImsStreamDirection direction, int bitsPerSecond) override;
+
+    virtual ndk::ScopedAStatus triggerImsDeregistration(RadioIndicationType type) override;
 };
 
 // The main test class for Radio AIDL Ims.