make it clear mGpuMemTotalMap is R/O

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I0484c629a02b84b59ca19b35e24a6496fbfd0990
diff --git a/services/gpuservice/tests/unittests/TestableGpuMem.h b/services/gpuservice/tests/unittests/TestableGpuMem.h
index 6c8becb..f21843f 100644
--- a/services/gpuservice/tests/unittests/TestableGpuMem.h
+++ b/services/gpuservice/tests/unittests/TestableGpuMem.h
@@ -28,7 +28,7 @@
 
     void setInitialized() { mGpuMem->mInitialized.store(true); }
 
-    void setGpuMemTotalMap(bpf::BpfMap<uint64_t, uint64_t>& map) {
+    void setGpuMemTotalMap(bpf::BpfMapRO<uint64_t, uint64_t>& map) {
         mGpuMem->setGpuMemTotalMap(map);
     }