Upgrade VNDK version to 4

Change-Id: I5566a1ef857f7db6c1dc04fcf16aa16fb6e1063a
diff --git a/bluetooth/audio/utils/Android.bp b/bluetooth/audio/utils/Android.bp
index 75081d6..e7659a4 100644
--- a/bluetooth/audio/utils/Android.bp
+++ b/bluetooth/audio/utils/Android.bp
@@ -78,7 +78,7 @@
     shared_libs: [
         "libbase",
         "libbinder_ndk",
-        "android.hardware.bluetooth.audio-V3-ndk",
+        "android.hardware.bluetooth.audio-V4-ndk",
         "libxml2",
     ],
     test_suites: [