Bug 20663: Remove dead code related to compound reports

Bug 20663: Remove dead code related to compound reports

TEST PLAN
---------
git grep "Create Compound Report"
-- only one file
git grep compound | grep 1
-- this is the only setting of the compound tt variable
less koha-tmpl/intranet-tmpl/prog/en/modules/reports/guided_reports_start.tt
-- There is an TT IF statement for compound.
-- In that statement it would trigger 'Save Compound'
git grep save_compound
-- only the template and the guided report perl
git grep create_compound
-- only triggered by the save code in the guided report perl
-- in the export for the C4/Reports/Guided.pm
git grep run_compound
-- left over in export

apply the patch
look around and see the pieces are cleaned up.

run koha qa test tools

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>