KVM: arm64: Move device mapping management into kvm_s2_fault_pin_pfn()

KVM: arm64: Move device mapping management into kvm_s2_fault_pin_pfn()

Attributes computed for devices are computed very late in the fault
handling process, meanning they are mutable for that long.

Introduce both 'device' and 'map_non_cacheable' attributes to the
vma_info structure, allowing that information to be set in stone
earlier, in kvm_s2_fault_pin_pfn().

Tested-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>