chansrv: drop g_sent_flag, not very useful and some clients skip acks
chansrv: drop g_sent_flag, not very useful and some clients skip acks

PKRoma/xrdp,metalefty/xrdp,neutrinolabs/xrdp,PKRoma/xrdp,metalefty/xrdp,PKRoma/xrdp,neutrinolabs/xrdp,metalefty/xrdp,neutrinolabs/xrdp