update.sh: Remove existing entries for the three FEODO_ tracker lists

update.sh: Remove existing entries for the three FEODO_ tracker lists

- This removes any time entries in the modified file for either FEODO_RECOMMENDED,
   FEODO_IP or FEODO_AGGRESSIVE.
- This also removes any blocklists for any of these sources from the /var/lib/ipblocklist
   directory.
- This patch will ensure that any reference to any of these sources is removed from the
   ipblocklist files.

Signed-off-by: Adolf Belka <adolf.belka@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>