fix link error for demo_server and demo_client (#414)

* add undef to fix windows compile error

* fix link error for demo_server and demo_client

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Co-authored-by: SKY-20230424HUG\Administrator <[email protected]>

Author: pengyutang125

demo/demo_client.c

@@ -25,6 +25,7 @@
 #pragma comment(lib,"ws2_32.lib")
 #pragma comment(lib,"event.lib")
 #pragma comment(lib, "Iphlpapi.lib")
+#pragma comment(lib, "Bcrypt.lib")
 #include "../tests/getopt.h"
 #else
 #include <sys/socket.h>

demo/demo_server.c

@@ -25,6 +25,7 @@
 #pragma comment(lib,"ws2_32.lib")
 #pragma comment(lib,"event.lib")
 #pragma comment(lib, "Iphlpapi.lib")
+#pragma comment(lib, "Bcrypt.lib")
 #endif