[CMake] fix CMP0115

src/CMakeLists.txt

@@ -47,7 +47,7 @@ SET(plugins
 
 FOREACH(plugin ${plugins})
   GET_FILENAME_COMPONENT(LIBRARY_NAME ${plugin} NAME)
-  ADD_LIBRARY(${LIBRARY_NAME} SHARED ${plugin})
+  ADD_LIBRARY(${LIBRARY_NAME} SHARED "${plugin}.cpp")
 
   IF(SUFFIX_SO_VERSION)
     SET_TARGET_PROPERTIES(${LIBRARY_NAME} PROPERTIES SOVERSION ${PROJECT_VERSION})