[sohu] fix extractor conflict

certain URL would cause conflict between SohuPlaylistIE and SohuIE

youtube_dl/extractor/sohu.py

@@ -262,7 +262,7 @@ class SohuIE(InfoExtractor):
 
 
 class SohuPlaylistIE(InfoExtractor):
-    _VALID_URL = r'https?://(?:my\.)?tv\.sohu\.com/pl/(?P<pl_id>\d+)'
+    _VALID_URL = r'https?://(?:my\.)?tv\.sohu\.com/pl/(?P<pl_id>\d+)$'
     _URL_IN_PLAYLIST = re.compile(r'<strong>.*?</strong>')
     parser = HTMLAttributeParser()
     _TESTS = [{
@@ -321,4 +321,3 @@ class SohuPlaylistIE(InfoExtractor):
                 r'<ul class="uList cfix">(.*?)</ul>',
                 webpage, 'video list', NO_DEFAULT, True, re.DOTALL)
         return video_list
-