x86_iommu/amd: make the address space naming consistent with intel-iommu

x86_iommu/amd: make the address space naming consistent with intel-iommu

To be consistent with intel-iommu:

- rename the address space to use '_' instead of '-'
- update the memory region relationships

Signed-off-by: Brijesh Singh <[email protected]>
Reviewed-by: Peter Xu <[email protected]>
Cc: Peter Xu <[email protected]>
Cc: "Michael S. Tsirkin" <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Richard Henderson <[email protected]>
Cc: Eduardo Habkost <[email protected]>
Cc: Marcel Apfelbaum <[email protected]>
Cc: Tom Lendacky <[email protected]>
Cc: Suravee Suthikulpanit <[email protected]>
Reviewed-by: Michael S. Tsirkin <[email protected]>
Signed-off-by: Michael S. Tsirkin <[email protected]>