[Gamekings] Fix order of replacement string

Oops.

youtube_dl/extractor/gamekings.py

@@ -32,7 +32,7 @@ class GamekingsIE(InfoExtractor):
         # Todo: add medium format
         video_url = video_url.replace(video_id, 'large/' + video_id)
         if not (self._is_valid_url(video_url, video_id)):
-            video_url = video_url.replace(video_id + 'large/', video_id)
+            video_url = video_url.replace('large/' + video_id, video_id)
 
         return {
             'id': video_id,