iommu/amd: Fix pci device refcount leak in ppr_notifier()

iommu/amd: Fix pci device refcount leak in ppr_notifier()

[ Upstream commit 3543723cdb71cfc2366a46f373f7a7f5c4af6e10 ]

As comment of pci_get_domain_bus_and_slot() says, it returns
a pci device with refcount increment, when finish using it,
the caller must decrement the reference count by calling
pci_dev_put(). So call it before returning from ppr_notifier()
to avoid refcount leak.

Fixes: b775c0c104f2 ("iommu/amd: Don't copy GCR3 table root pointer")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221118093604.216371-1-yangyingliang@huawei.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>