cmake LWS_HAVE_OPENSSL_STACK examples

warmcat/libwebsockets lib/tls/CMakeLists.txt :369 

CHECK_C_SOURCE_COMPILES("#include <openssl/ssl.h>\nint main(void) { OPENSSL_STACK *x = NULL; return !x; } \n" LWS_HAVE_OPENSSL_STACK)

c-jimenez/open-ocpp 3rdparty/libwebsockets/lib/tls/CMakeLists.txt :364 

CHECK_C_SOURCE_COMPILES("#include <openssl/ssl.h>\nint main(void) { OPENSSL_STACK *x = NULL; return !x; } \n" LWS_HAVE_OPENSSL_STACK)