BatteryStats: explicitly copy the wakeup reasons

As the wakeup reasons received from binder callback are in const
reference, std::move the parameter will result in a copy operation in
order to fulfill the const restriction. Update to reflect this
explicitly.

Test: adb shell dumpsys batterystats --history
Bug: 173165219
Change-Id: I6ab995cc11600b37123651bacc2015a3bf1a4bf6

services/core/jni/com_android_server_am_BatteryStatsService.cpp

@@ -124,7 +124,7 @@ public:
         {
             std::unique_lock<std::mutex> reasonsLock(mReasonsMutex, std::defer_lock);
             if (reasonsLock.try_lock() && mWakeupReasons.empty()) {
-                mWakeupReasons = std::move(wakeupReasons);
+                mWakeupReasons = wakeupReasons;
                 reasonsCaptured = true;
             }
         }