package/proftpd: security bump to version 1.3.6e

package/proftpd: security bump to version 1.3.6e

1.3.6e
---------
  + Fixed null pointer deference in mod_sftp when using SCP incorrectly
    (Issue #1043).

1.3.6d
---------
  + Fixed issue with FTPS uploads of large files using TLSv1.3 (Issue #959).

1.3.6c
---------
  + Fixed regression in directory listing latency (Issue #863).
  + Detect OpenSSH-specific formatted SFTPHostKeys, and log hint for
    converting them to supported format.
  + Fixed use-after-free vulnerability during data transfers (Issue #903)
    [CVE-2020-9273]
  + Fixed out-of-bounds read in mod_cap by updating the bundled libcap
    (Issue #902) [CVE-2020-9272]

http://proftpd.org/docs/RELEASE_NOTES-1.3.6e

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
[Peter: mark as security bump, add CVEs]
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>