package/clamav: security bump to version 0.103.2

package/clamav: security bump to version 0.103.2

Fixes the following security issues:

- CVE-2021-1386: Fix for UnRAR DLL load privilege escalation.  Affects
  0.103.1 and prior on Windows only.

- CVE-2021-1252: Fix for Excel XLM parser infinite loop.  Affects 0.103.0
  and 0.103.1 only.

- CVE-2021-1404: Fix for PDF parser buffer over-read; possible crash.
  Affects 0.103.0 and 0.103.1 only.

- CVE-2021-1405: Fix for mail parser NULL-dereference crash.  Affects
  0.103.1 and prior.

- CVE-2021-27506: The ClamAV Engine (Version 0.103.1 and below) embedded in
  Storsmshield Network Security (1.0 to 4.1.5) is subject to DoS in case of
  parsing of malformed png files.

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>