Fix typo in Engine::getDevicesForProductStrategy.

Bug: 215694958
Test: atest AudioServiceHostTest
Change-Id: I14760ffb76b691a99d40fa1120d440bd03d9d0de
diff --git a/services/audiopolicy/enginedefault/src/Engine.cpp b/services/audiopolicy/enginedefault/src/Engine.cpp
index c73c17d..622be7a 100644
--- a/services/audiopolicy/enginedefault/src/Engine.cpp
+++ b/services/audiopolicy/enginedefault/src/Engine.cpp
@@ -645,7 +645,7 @@
         // there is a preferred device, is it available?
         preferredAvailableDevVec =
                 availableOutputDevices.getDevicesFromDeviceTypeAddrVec(preferredStrategyDevices);
-        if (preferredAvailableDevVec.size() == preferredAvailableDevVec.size()) {
+        if (preferredAvailableDevVec.size() == preferredStrategyDevices.size()) {
             ALOGVV("%s using pref device %s for strategy %u",
                    __func__, preferredAvailableDevVec.toString().c_str(), strategy);
             return preferredAvailableDevVec;