options: deprecate some other complex --ad/--vd features

Who even needs those?

Once these deprecations are gone, --ad/--vd are simple lists without any
kind of complex matching.

DOCS/interface-changes.rst

@@ -46,6 +46,7 @@ Interface changes
     - change how spdif codecs are selected. You can't enable spdif passthrough
       with --ad anymore. This was deprecated; use --audio-spdif instead.
     - deprecate the "family" selection with --ad/--vd
+      forcing/excluding codecs with "+", "-", "-" is deprecated as well
     - explicitly mark --ad-spdif-dtshd as deprecated (it was done so a long time
       ago, but it didn't complain when using the option)
  --- mpv 0.22.0 ---

DOCS/man/options.rst

@@ -1145,9 +1145,10 @@ Audio
     ``-`` at the end of the list suppresses fallback on other available
     decoders not on the ``--ad`` list. ``+`` in front of an entry forces the
     decoder. Both of these should not normally be used, because they break
-    normal decoder auto-selection!
+    normal decoder auto-selection! Both of these methods are deprecated.
 
-    ``-`` in front of an entry disables selection of the decoder.
+    ``-`` in front of an entry disables selection of the decoder. This is
+    deprecated.
 
     .. admonition:: Examples
 

common/codecs.c

@@ -92,11 +92,14 @@ struct mp_decoder_list *mp_select_decoders(struct mp_log *log,
         bstr entry;
         bstr_split_tok(sel, ",", &entry, &sel);
         if (bstr_equals0(entry, "-")) {
+            mp_warn(log, "Excluding codecs is deprecated.\n");
             stop = true;
             break;
         }
         bool force = bstr_eatstart0(&entry, "+");
         bool exclude = !force && bstr_eatstart0(&entry, "-");
+        if (exclude || force)
+            mp_warn(log, "Forcing or excluding codecs is deprecated.\n");
         struct mp_decoder_list *dest = exclude ? remove : list;
         bstr family, decoder;
         if (bstr_split_tok(entry, ":", &family, &decoder)) {