Bug 18716: Remove CGI::param warns from updatesupplier.pl

This script floods the logs with this kind of warnings.

To test:
- Run:
  $ koha-plack-err
- Edit a vendor in the acquisitions module
- Save
=> FAIL: Logs show lots of warnings that look like:
 CGI::param called in list context from package CGI::Compile::ROOT::home_vagrant_kohaclone_acqui_updatesupplier_2epl
- Apply this patch
- Run:
  $ restart_all
  $ koha-plack-err
- Edit a vendor, add/delete vendor contacts
=> SUCESS: No more warnings
- Verify editing and storing vendor contacts works as expected.
- Sign off :-D

Signed-off-by: Marc Véron <veron@veron.ch>

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
(cherry picked from commit c359329234)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
(cherry picked from commit 9c2d9c89a4)
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>

acqui/updatesupplier.pl

@@ -98,7 +98,7 @@ my @contacts;
 my %contact_info;
 
 foreach (qw(id name position phone altphone fax email notes orderacquisition claimacquisition claimissues acqprimary serialsprimary)) {
-    $contact_info{$_} = [ $input->param('contact_' . $_) ];
+    $contact_info{$_} = [ $input->multi_param('contact_' . $_) ];
 }
 
 for my $cnt (0..scalar(@{$contact_info{'id'}})) {