Bug 38158: Typo in inventory 'Items has no "not for loan" status'

Bug 38158: Typo in inventory 'Items has no "not for loan" status'

This patch corrects a typo in the inventory tool when an inventory
is done against not for loan items and an item has no not for loan
status.

To test:
1. Go to Cataloging > Inventory
2. Enter a barcode for an item that has items.notforloan = 0 in the "Or scan items one by one" text box
3. Check all the boxes EXCEPT "For loan" under "Optional filters for inventory list or comparing barcodes" > "items.notforloan"
4. Click "Submit"
   --> In the "Problems" column, it says "Items has no "not for loan" status"
5. Apply patch
6. Reload the page
   --> In the "Problems" column, "Item" should now be singular

Signed-off-by: Sam Sowanick <sam.sowanick@corvallisoregon.gov>
Signed-off-by: Emily Lamancusa <emily.lamancusa@montgomerycountymd.gov>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>