Bug 27586: Import patrons script has a confirm switch that doesn't nothing!

Bug 27586: Import patrons script has a confirm switch that doesn't nothing!

If the script misc/import_patrons.pl is run without "--confirm" it reports
that it is "running in dry-run mode" but it is not!

Test Plan:
1) Import a CSV of patrons using import_patrons.pm *without* the --confirm parameter
2) Note that it does actually import the patrons
3) Apply this patch
4) Note that this time the patrons are not actually imported
5) Import again with --confirm
6) Note that the patrons were actually imported this time!

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>