Fix the comment of AIBinder_setMinSchedulerPolicy.

The second parameter is the priority, cannot be 20, which would be lower priority than the lowest priority that can exist.

Bugs: me
Change-Id: Ic990d0f365fb907fe252944991362e8729664562
Test: N/A
diff --git a/tests/extension/vibrator/aidl/default/CustomVibrator.cpp b/tests/extension/vibrator/aidl/default/CustomVibrator.cpp
index 7a7c58b..9c306b5 100644
--- a/tests/extension/vibrator/aidl/default/CustomVibrator.cpp
+++ b/tests/extension/vibrator/aidl/default/CustomVibrator.cpp
@@ -60,7 +60,7 @@
 ndk::SpAIBinder CustomVibrator::createBinder() {
     auto binder = BnCustomVibrator::createBinder();
     // e.g. AIBinder_setInheritRt(binder.get(), true);
-    // e.g. AIBinder_setMinSchedulerPolicy(binder.get(), SCHED_NORMAL, 20);
+    // e.g. AIBinder_setMinSchedulerPolicy(binder.get(), SCHED_NORMAL, -2);
     // e.g. AIBinder_setRequestingSid(binder.get(), true);
     return binder;
 }