Disable key repeat if key catcher is 0

SDL1.2 branch disables key repeat when key catcher is 0.
Presumably to prevent binds from executing multiple times.

SDL2 replaced being able to disabled key repeat using SDL_EnableKeyRepeat
with a non-zero repeat value in the key event.

code/sdl/sdl_input.c

@@ -726,6 +726,9 @@ static void IN_ProcessEvents( void )
 		switch( e.type )
 		{
 			case SDL_KEYDOWN:
+				if ( e.key.repeat && Key_GetCatcher( ) == 0 )
+					break;
+
 				if( ( key = IN_TranslateSDLToQ3Key( &e.key.keysym, qtrue ) ) )
 					Com_QueueEvent( 0, SE_KEY, key, qtrue, 0, NULL );