add: luat_libs.h添加websocket库的声明

luat/include/luat_libs.h

@@ -134,4 +134,6 @@ LUAMOD_API int luaopen_protobuf( lua_State *L );
 LUAMOD_API int luaopen_httpsrv( lua_State *L );
 LUAMOD_API int luaopen_rsa( lua_State *L );
 
+LUAMOD_API int luaopen_websocket( lua_State *L );
+
 #endif