client: Reset pending_call_state on disconnect

Fixes T251

Signed-off-by: Jakub Jelen <jjelen@redhat.com>
Reviewed-by: Anderson Toshiyuki Sasaki <ansasaki@redhat.com>
(cherry picked from commit 5348267fa8)

src/client.c

@@ -721,6 +721,7 @@ error:
   }
   session->opts.fd = SSH_INVALID_SOCKET;
   session->session_state=SSH_SESSION_STATE_DISCONNECTED;
+  session->pending_call_state = SSH_PENDING_CALL_NONE;
 
   while ((it=ssh_list_get_iterator(session->channels)) != NULL) {
     ssh_channel_do_free(ssh_iterator_value(ssh_channel,it));