cmake LWS_HAVE_STRING_H examples

warmcat/libwebsockets CMakeLists.txt :675 

CHECK_C_SOURCE_COMPILES("#include <string.h>\nvoid main(void) { while(1) ; } void xxexit(void){}" LWS_HAVE_STRING_H)

c-jimenez/open-ocpp 3rdparty/libwebsockets/CMakeLists.txt :639 

CHECK_INCLUDE_FILE(string.h LWS_HAVE_STRING_H)

fluffos/fluffos src/thirdparty/libwebsockets/CMakeLists.txt :622 

CHECK_INCLUDE_FILE(string.h LWS_HAVE_STRING_H)