use alive_sleep() from sleep command

git-svn-id: svn://svn.berlios.de/openocd/trunk@939 b42882b7-edfa-0310-969c-e2dbd0fdcd60

src/helper/command.c

@@ -693,7 +693,7 @@ int handle_sleep_command(struct command_context_s *cmd_ctx, char *cmd, char **ar
 	if (argc == 1)
 	{
 		duration = strtoul(args[0], NULL, 0);
-		usleep(duration * 1000);
+		alive_sleep(duration);
 	}
 
 	return ERROR_OK;