[CMake] use COMPUTE_PROJECT_ARGS

CMakeLists.txt

@@ -21,8 +21,8 @@ INCLUDE(cmake/sphinx.cmake)
 
 SET(PKG_CONFIG_ADDITIONAL_VARIABLES plugindir ${PKG_CONFIG_ADDITIONAL_VARIABLES})
 
-CMAKE_POLICY(SET CMP0048 OLD)
-PROJECT(${PROJECT_NAME} CXX)
+COMPUTE_PROJECT_ARGS(PROJECT_ARGS LANGUAGES CXX)
+PROJECT(${PROJECT_NAME} ${PROJECT_ARGS})
 
 FINDPYTHON()
 INCLUDE_DIRECTORIES(SYSTEM ${PYTHON_INCLUDE_DIRS})