Remove unnecessary std::move

Moving a temporary object prevents copy elision, and could reduce
performance.

This fixes -Wpessimizing-move compiler warning.

Test: presubmit
Bug: 154270751
Change-Id: Ia0b02d90c239572c953007272f75900ee77c6305
diff --git a/services/mediaresourcemanager/ResourceManagerMetrics.cpp b/services/mediaresourcemanager/ResourceManagerMetrics.cpp
index a8a1de1..8b3711c 100644
--- a/services/mediaresourcemanager/ResourceManagerMetrics.cpp
+++ b/services/mediaresourcemanager/ResourceManagerMetrics.cpp
@@ -821,7 +821,7 @@
     metricsLog += getAppsPixelCount(mProcessPixelsMap);
     metricsLog += getAppsCodecUsageMetrics(mProcessConcurrentCodecsMap);
 
-    return std::move(metricsLog);
+    return metricsLog;
 }
 
 } // namespace android