meta-ampere: update PSU1 name in phosphor-gpio-present

This corrects the name of the PSU from CPU1 to PSU1.

Tested:
1. Get PSUs name
   busctl get-property xyz.openbmc_project.Inventory.Manager \
   /xyz/openbmc_project/inventory/system/powersupply/PowerSupply0 \
   xyz.openbmc_project.Inventory.Item PrettyName
   s "PSU0"
   busctl get-property xyz.openbmc_project.Inventory.Manager \
   /xyz/openbmc_project/inventory/system/powersupply/PowerSupply1 \
   xyz.openbmc_project.Inventory.Item PrettyName
   s "PSU1"

Signed-off-by: Hieu Huynh <hieuh@os.amperecomputing.com>
Change-Id: I3e1110d3b76335d7412006f75e79073f9f776151