[orf:radio] Fix extraction

Since oe1.orf.at has been updated, both ORF radios supported by youtube_dl
use the same API. This commit honors this fact by merging both extractors
into one.

youtube_dl/extractor/extractors.py

@@ -736,8 +736,8 @@ from .openload import OpenloadIE
 from .ora import OraTVIE
 from .orf import (
     ORFTVthekIE,
-    ORFOE1IE,
     ORFFM4IE,
+    ORFOE1IE,
     ORFIPTVIE,
 )
 from .packtpub import (