Fix last remains of our commit-merge-revert-mess about #96

 #96, elected best bug of 2017 !

hardware_provisioning/admin.py

@@ -167,7 +167,7 @@ class LoanInline(admin.TabularInline):
     model = Loan
     extra = 0
     exclude = ('notes',)
-    readonly_fields = ('item', 'get_mac_or_serial', 'loan_date', 'loan_date_end', 'is_running')
+    readonly_fields = ('item', 'get_mac_and_serial', 'loan_date', 'loan_date_end', 'is_running')
 
     show_change_link = True