cmake HAVE_XSS examples

htcondor/htcondor build/cmake/CondorConfigure.cmake :454 

find_library(HAVE_XSS Xss)

psi-im/psi src/tools/CMakeLists.txt :163 

target_compile_definitions(tools PRIVATE HAVE_XSS)

visualboyadvance-m/visualboyadvance-m src/wx/CMakeLists.txt :477 

target_compile_definitions(visualboyadvance-m PRIVATE HAVE_XSS)