HeadTracking: Make QuarternionUtil.h available

Required to interpret Pose data outside of libheadtracking.

Test: atest libheadtracking-test
Bug: 269620212
Change-Id: I9a20008d985f8b9448149c12815bc5e76fb2186f
diff --git a/media/libheadtracking/QuaternionUtil-test.cpp b/media/libheadtracking/QuaternionUtil-test.cpp
index e79e54a..ebb4223 100644
--- a/media/libheadtracking/QuaternionUtil-test.cpp
+++ b/media/libheadtracking/QuaternionUtil-test.cpp
@@ -16,7 +16,7 @@
 
 #include <gtest/gtest.h>
 
-#include "QuaternionUtil.h"
+#include "media/QuaternionUtil.h"
 #include "TestUtil.h"
 
 using Eigen::Quaternionf;