Bug 28674: Fix typo 'hlpd' in schema comments

Bug 28674: Fix typo 'hlpd' in schema comments

Fixes the lines for old_reserves.item_level_hold and
reserves.item_level_hold comments to read 'hold'
instead of 'hpld'

To test:
* The easiest way to verify this change is by looking
at the patch itself

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
(cherry picked from commit 241ea0834849e445816bfab8d5d52ea9b1e25de6)
Signed-off-by: Jacob O'Mara <jacob.omara@ptfs-europe.com>