removing mad123

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

mad123 is a mpg123 replacement that uses libmad, i.e. uses fixed point
math. It's last release was from 2005, and according to repology,
we're the only distribution packaging it.

It broke due to a recent curl update and now dies with:

--- mp3_stream.o ---
In file included from mp3_stream.c:33:0:
In function 'mps_url_spawn_reader',
    inlined from 'mps_url_open' at mp3_stream.c:563:3:
/tmp/audio/mad123/work/.buildlink/include/curl/typecheck-gcc.h:50:15: error: call to '_curl_easy_setopt_err_long' declared with attribute warning: curl_easy_setopt expects a long argument [-Werror]
               _curl_easy_setopt_err_long();                             \
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/tmp/audio/mad123/work/.buildlink/include/curl/curl.h:59:49: note: in definition of macro 'CURL_IGNORE_DEPRECATION'
 #define CURL_IGNORE_DEPRECATION(statements)     statements
                                                 ^~~~~~~~~~
mp3_stream.c:648:2: note: in expansion of macro 'curl_easy_setopt'
  curl_easy_setopt(ch, CURLOPT_NOPROGRESS, 1);
  ^~~~~~~~~~~~~~~~
/tmp/audio/mad123/work/.buildlink/include/curl/typecheck-gcc.h:50:15: error: call to '_curl_easy_setopt_err_long' declared with attribute warning: curl_easy_setopt expects a long argument [-Werror]
               _curl_easy_setopt_err_long();                             \
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/tmp/audio/mad123/work/.buildlink/include/curl/curl.h:59:49: note: in definition of macro 'CURL_IGNORE_DEPRECATION'
 #define CURL_IGNORE_DEPRECATION(statements)     statements
                                                 ^~~~~~~~~~
mp3_stream.c:649:2: note: in expansion of macro 'curl_easy_setopt'
  curl_easy_setopt(ch, CURLOPT_FAILONERROR, 1);
  ^~~~~~~~~~~~~~~~
/tmp/audio/mad123/work/.buildlink/include/curl/typecheck-gcc.h:50:15: error: call to '_curl_easy_setopt_err_long' declared with attribute warning: curl_easy_setopt expects a long argument [-Werror]
               _curl_easy_setopt_err_long();                             \
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/tmp/audio/mad123/work/.buildlink/include/curl/curl.h:59:49: note: in definition of macro 'CURL_IGNORE_DEPRECATION'
 #define CURL_IGNORE_DEPRECATION(statements)     statements
                                                 ^~~~~~~~~~
mp3_stream.c:650:2: note: in expansion of macro 'curl_easy_setopt'
  curl_easy_setopt(ch, CURLOPT_FOLLOWLOCATION, 1);
  ^~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors


I suggest removing it, but if someone fixes it instead, that's fine
with me too.
 Thomas