DOCS/man/input: note that stream-open-filename is not normalized

Since 38ad1ed path is normalized but stream-open-filename is not, so
update the docs where it says that they are the same.

Author: guidocella

DOCS/man/input.rst

@@ -2156,13 +2156,14 @@ Property list
     Full absolute path of the currently played file.
 
 ``stream-open-filename``
-    The full path to the currently played media. This is different from
-    ``path`` only in special cases. In particular, if ``--ytdl=yes`` is used,
-    and the URL is detected by ``youtube-dl``, then the script will set this
-    property to the actual media URL. This property should be set only during
-    the ``on_load`` or ``on_load_fail`` hooks, otherwise it will have no effect
-    (or may do something implementation defined in the future). The property is
-    reset if playback of the current media ends.
+    The path to the currently played media. If ``--ytdl=yes`` is used, and the
+    URL is detected by ``youtube-dl``, then the script will set this property to
+    the actual media URL. Otherwise, this is the path as it was passed on the
+    command line for single files, unlike ``path`` which is normalized. This
+    property should be set only during the ``on_load`` or ``on_load_fail``
+    hooks, otherwise it will have no effect (or may do something implementation
+    defined in the future). The property is reset if playback of the current
+    media ends.
 
 ``media-title``
     If the currently played file has a ``title`` tag, use that.