Bug 18919: Repair "Transaction branch" in cash_register_stats.pl

Bug 18919: Repair "Transaction branch" in cash_register_stats.pl

- values of the option fields are now correctly loaded

TEST PLAN:
go to domain/cgi-bin/koha/reports/cash_register_stats.pl
1 - Make a report for all branches => it works
2 - Make a report for any branch => you will get the same or no result
3 - apply patch
4 - Repeat 2 => it should work

Followed test plan worked as intended
Signed-off-by: Alex Buckley <alexbuckley@catalyst.net.nz>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>