* doc/org-manual.org: Clarify :results file link with no :file

(Type):
(Format): Document that :results file link is using the source block
result as file path when :file header argument is not present.

Reported-by: dalanicolai <dalanicolai@gmail.com>
Link: https://orgmode.org/list/CACJP=3=HrzaB+b2bTk2=-hrcv0STx41eFjedgtp=qXvGjVJQWA@mail.gmail.com

doc/org-manual.org

@@ -18351,6 +18351,9 @@ described in the documentation for individual languages.  See
   from the =file-ext= header argument.  In that case, both the name
   and the extension are mandatory.
 
+  Result can also be interpreted as path to file.  See =:results
+  link=.
+
   #+begin_example
   ,#+name: circle
   ,#+BEGIN_SRC asymptote :results value file :file-ext pdf
@@ -18431,6 +18434,9 @@ follows from the type specified above.
   [[file:org-mode-unicorn.svg]]
   #+end_example
 
+  If =:file= header argument is omitted, interpret source block result
+  as the file path.
+
 - =org= ::
 
   Results enclosed in a =BEGIN_SRC org= block.  For comma-escape,