iommu/amd: Introduce per PCI segment device table size

iommu/amd: Introduce per PCI segment device table size

With multiple pci segment support, number of BDF supported by each
segment may differ. Hence introduce per segment device table size
which depends on last_bdf. This will replace global
"device_table_size" variable.

Co-developed-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
Link: https://lore.kernel.org/r/20220706113825.25582-12-vasant.hegde@amd.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>