[vimeo] Do not fail when no hls formats

youtube_dl/extractor/vimeo.py

@@ -403,7 +403,10 @@ class VimeoIE(VimeoBaseInfoExtractor):
         formats = []
         m3u8_url = config_files.get('hls', {}).get('all')
         if m3u8_url:
-            formats = self._extract_m3u8_formats(m3u8_url, video_id, 'mp4', 'm3u8_native', 0, 'hls', fatal=False)
+            m3u8_formats = self._extract_m3u8_formats(
+                m3u8_url, video_id, 'mp4', 'm3u8_native', 0, 'hls', fatal=False)
+            if m3u8_formats:
+                formats.append(m3u8_formats)
         for key in ('other', 'sd', 'hd'):
             formats += files[key]
         self._sort_formats(formats)