Enable key repeat in automap

Key repeat has been disabled in the automap since key repeat was first
defined in 96782e0.  Internal
handling produces mostly the right result, but the F9/F10 handling for
zooming the map does not repeat, so users must repeatedly press,
release, and re-press the key to zoom by multiple steps.  Enable
repetition so that the user can press-and-hold F9/F10 to zoom the map.

Reported-by: dxx-rebirth#539
Suggested-by: InfernalCore <dxx-rebirth#539 (comment)>

similar/main/automap.cpp

@@ -1138,7 +1138,7 @@ window_event_result automap::event_handler(const d_event &event)
 		case event_type::window_activated:
 			game_flush_inputs(controls);
 			event_toggle_focus(1);
-			key_toggle_repeat(0);
+			key_toggle_repeat(1);
 			break;
 
 		case event_type::window_deactivated: