RTMP streams and '--max-filesize'

[Gisle Vanem via curl-users]

I've been building libcurl + curl with 'USE_LIBRTMP'.
But not with any crypto since the latest Rtmp v.2.3 is
hopelessly outdated when it comes to current OpenSSL/mbedTLS.

Anyway, this test works fine:
curl -o test.flv --max-filesize 10000000 rtmp://ossrs.net/live/livestream

Except that the 'test.flv' is way larger than the given
'--max-filesize'. I guess it does not make sense for an endless
stream.

But I'm annoyed that I cannot say "--max-filesize 10M".
Attached is a patch for that.