[formatsort] Remove misuse of 'preference'

'preference' is to be used only when the format is better that ALL qualities of a lower preference irrespective of ANY sorting order the user requests. See deezer.py for correct use of this

In the older sorting method, `preference`, `quality` and `language_preference` were functionally almost equivalent. So these disparities doesn't really matter there

Also, despite what the documentation says, the default for `preference` was actually 0 and not -1. I have tried to correct this and also account for it when converting `preference` to `quality`

youtube_dlc/extractor/soundcloud.py

@@ -422,7 +422,7 @@ class SoundcloudIE(InfoExtractor):
                         'ext': urlhandle_detect_ext(urlh) or 'mp3',
                         'filesize': int_or_none(urlh.headers.get('Content-Length')),
                         'url': format_url,
-                        'preference': 10,
+                        'quality': 10,
                     })
 
         def invalid_url(url):