Fix crash in CShoutcastFile::Close(), clear buffer pointer after delete.
Fix ticket 12729, ignore content-length of shoutcast file.
When the shoutcast file was 302 redirected, libcurl may return the
content-length of the 302 page's body, it cause next read return 0.
Merge pull request #2307 from ulion/fix_redirected_shoutcast_ticket_12729

Fix redirected shoutcast ticket 12729