Bug 20903: Remove unnecessary category code parameters

Bug 20903: Remove unnecessary category code parameters

Test plan:
0) Do no apply the patch
1) Have only one adults patrons category defined
2) Add a fine to child patron and pay it
3) Try to print the payment receipt (file printfeercpt.pl)
4) You see only ISE
5) Apply the patch
6) Try the printing again
7) Now you should see right receipt

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 5f03b21cf3a7141dc0f2ae2b1922505d55d4cd34)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>