Merge pull request #3615 from Alexander-Wilms/cmake-sdl2

Fix SDL2MAIN_LIBRARY CMake warning

cmake_modules/FindSDL2.cmake

@@ -314,13 +314,6 @@ FIND_PACKAGE_HANDLE_STANDARD_ARGS(SDL2
                                   REQUIRED_VARS SDL2_LIBRARY SDL2_INCLUDE_DIR
                                   VERSION_VAR SDL2_VERSION_STRING)
 
-if(SDL2MAIN_LIBRARY)
-  FIND_PACKAGE_HANDLE_STANDARD_ARGS(SDL2main
-                                    REQUIRED_VARS SDL2MAIN_LIBRARY SDL2_INCLUDE_DIR
-                                    VERSION_VAR SDL2_VERSION_STRING)
-endif()
-
-
 mark_as_advanced(SDL2_PATH
                  SDL2_NO_DEFAULT_PATH
                  SDL2_LIBRARY