Keep target sorted

Author: erjiaqing

src/adaptations/device-layer/Makefile.am

@@ -163,14 +163,14 @@ libDeviceLayer_a_SOURCES               +=       \
     ESP32/Entropy.cpp                           \
     ESP32/ESP32Config.cpp                       \
     ESP32/ESP32Utils.cpp                        \
-    ESP32/ThreadStackManagerImpl.cpp            \ 
     ESP32/GroupKeyStoreImpl.cpp                 \
     ESP32/Logging.cpp                           \
     ESP32/LwIPCoreLock.cpp                      \
     ESP32/NetworkProvisioningServerImpl.cpp     \
     ESP32/PlatformManagerImpl.cpp               \
     ESP32/SoftwareUpdateManagerImpl.cpp         \
     ESP32/SystemTimeSupport.cpp                 \
+    ESP32/ThreadStackManagerImpl.cpp            \ 
     OpenThread/OpenThreadUtils.cpp              \
     LwIP/WarmSupport.cpp                        \
     $(NULL)