Update to 7.21.3
    
    - New upstream release 7.21.3:
      - added --noconfigure switch to testcurl.pl
      - added --xattr option
      - added CURLOPT_RESOLVE and --resolve
      - added CURLAUTH_ONLY
      - added version-check.pl to the examples dir
      - check for libcurl features for some command line options
      - Curl_setopt: disallow CURLOPT_USE_SSL without SSL support
      - http_chunks: remove debug output
      - URL-parsing: consider ? a divider
      - SSH: avoid using the libssh2_ prefix
      - SSH: use libssh2_session_handshake() to work on win64
      - ftp: prevent server from hanging on closed data connection when stopping
        a transfer before the end of the full transfer (ranges)
      - LDAP: detect non-binary attributes properly
      - ftp: treat server's response 421 as CURLE_OPERATION_TIMEDOUT
      - gnutls->handshake: improved timeout handling
      - security: pass the right parameter to init
      - krb5: use GSS_ERROR to check for error
      - TFTP: resend the correct data
      - configure: fix autoconf 2.68 warning: no AC_LANG_SOURCE call detected
      - GnuTLS: now detects socket errors on Windows
      - symbols-in-versions: updated en masse
      - added a couple of examples that were missing from the tarball
      - Curl_send/recv_plain: return errno on failure
      - Curl_wait_for_resolv (for c-ares): correct timeout
      - ossl_connect_common: detect connection re-use
      - configure: prevent link errors with --librtmp
      - openldap: use remote port in URL passed to ldap_init_fd()
      - url: provide dead_connection flag in Curl_handler::disconnect
      - lots of compiler warning fixes
      - ssh: fix a download resume point calculation
      - fix getinfo CURLINFO_LOCAL* for reused connections
      - multi: the returned running handles counter could turn negative
      - multi: only ever consider pipelining for connections doing HTTP(S)
    - Drop upstream patches now in tarball
    - Update bz650255 and disable-test1112 patches to apply against new codebase
    - Add workaround for false-positive glibc-detected buffer overflow in tftpd
      test server with FORTIFY_SOURCE (similar to #515361)