pull remote user input even if we are doing a local choice.

this mainly effects wesnoth.synchronize_choices:
previously the client would not process incoming choices from other
players while it was exeucting its own local choice (usually a dialog).
The problem this commit fixes is that with the old behaviour any choice
from another player would block the incoming queue, in particular
chatmessages after that command would be delayed until the
wesnoth.synchronize_choices is finished.

(cherry-picked from commit edd7a82255)

src/synced_user_choice.cpp

@@ -425,7 +425,7 @@ std::map<int, config> user_choice_manager::get_user_choice_internal(const std::s
 
 void user_choice_manager::process(events::pump_info&)
 {
-	if(waiting())
+	if(!oos_ && !finished())
 	{
 		pull();
 	}