Fix VtsHalVibratorManagerTargetTest test fail

Adding the cancelSynced() once prepareSynced() was called and return ok.

Fix: 247687286
Test: atest VtsHalVibratorManagerTargetTest
Signed-off-by: Chase Wu <chasewu@google.com>
Change-Id: I91e08e92cb8e1399eb6acdbedf95958fbf44c393
diff --git a/vibrator/aidl/vts/VtsHalVibratorManagerTargetTest.cpp b/vibrator/aidl/vts/VtsHalVibratorManagerTargetTest.cpp
index 44fa3be..e8ed26a 100644
--- a/vibrator/aidl/vts/VtsHalVibratorManagerTargetTest.cpp
+++ b/vibrator/aidl/vts/VtsHalVibratorManagerTargetTest.cpp
@@ -96,6 +96,7 @@
     if (!(capabilities & IVibratorManager::CAP_SYNC)) return;
     if (vibratorIds.empty()) return;
     EXPECT_TRUE(manager->prepareSynced(vibratorIds).isOk());
+    EXPECT_TRUE(manager->cancelSynced().isOk());
 }
 
 TEST_P(VibratorAidl, PrepareSyncedEmptySetIsInvalid) {
@@ -208,6 +209,7 @@
         EXPECT_TRUE(manager->prepareSynced(vibratorIds).isOk());
         Status status = manager->triggerSynced(callback);
         EXPECT_TRUE(isUnknownOrUnsupported(status)) << status;
+        EXPECT_TRUE(manager->cancelSynced().isOk());
     }
 }