Bug 22529: Use new C4::Auth::haspermission from svc/members/search

Bug 22529: Use new C4::Auth::haspermission from svc/members/search

The svc/members/search script can be used to retrieve patrons with a
specific permission. This feature is only used once, to link patrons to
funds.
The code in the script is duplicated from what we have in
C4::Auth::haspermission, and it makes sense to clean it.

Test plan:
Create a fund and add users to this fund.
When you search for users you must only have a list of patrons with the
acquisition.order_manage permission.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Works as described. No errors
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>