aaudio: call validate() from readFromParcel()

This is to ensure that validate() is always called
in the future.

Bug: 74558178
Test: run AAudio CTS
Test: on Marlin, adb shell write_sine_callback -pl
Change-Id: I661f3c4e690be2268ca61b80a98bbdf9a7368c1b
diff --git a/media/libaaudio/src/binding/AudioEndpointParcelable.h b/media/libaaudio/src/binding/AudioEndpointParcelable.h
index aa8573f..e4f8b9e 100644
--- a/media/libaaudio/src/binding/AudioEndpointParcelable.h
+++ b/media/libaaudio/src/binding/AudioEndpointParcelable.h
@@ -56,8 +56,6 @@
 
     aaudio_result_t resolve(EndpointDescriptor *descriptor);
 
-    aaudio_result_t validate();
-
     aaudio_result_t close();
 
     void dump();
@@ -70,6 +68,8 @@
     RingBufferParcelable    mDownDataQueueParcelable;    // eg. playback
 
 private:
+    aaudio_result_t         validate() const;
+
     int32_t                 mNumSharedMemories = 0;
     SharedMemoryParcelable  mSharedMemories[MAX_SHARED_MEMORIES];
 };