openocd: fix issue in WIN32 with TCP adapters

Issue: server_quit is called before adapter_quit:
  In WIN32 only in server_quit we do an WSACleanup,
  which terminates/closes all active sockets.
  So if the adapter is TCP based, the adapter.quit handler
  will fail if it will need to send some commands through TCP.

Example: close_socket in jtag_vpi_quit will fail in WIN32
  because the socket is already closed
  and the errno is set as "Bad File Descriptor"

To fix that we introduced new functions called server_host_os_entry/quit
to manage specific OS setup (hence WSA for sockets in WINDOWS) in order
to delay WSACleanup after adapter_quit().

Change-Id: Ie4afacafe123857f6ae300e376bdfcf0d8c027ac
Signed-off-by: Tarek BOCHKATI <tarek.bouchkati@gmail.com>
Reviewed-on: http://openocd.zylin.com/5456
Tested-by: jenkins
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>

src/openocd.c

@@ -345,6 +345,8 @@ int openocd_main(int argc, char *argv[])
 	command_context_mode(cmd_ctx, COMMAND_CONFIG);
 	command_set_output_handler(cmd_ctx, configuration_output_handler, NULL);
 
+	server_host_os_entry();
+
 	/* Start the executable meat that can evolve into thread in future. */
 	ret = openocd_thread(argc, argv, cmd_ctx);
 
@@ -360,6 +362,8 @@ int openocd_main(int argc, char *argv[])
 
 	adapter_quit();
 
+	server_host_os_close();
+
 	/* Shutdown commandline interface */
 	command_exit(cmd_ctx);