mb/google/nissa/var/nivviks,yaviks: Add DmaProperty for ISH

On nissa, the ISH is running closed source firmware, so the ChromeOS
security requirements specify it must be behind an IOMMU. Add
DmaProperty to the ISH _DSD on nivviks and yaviks.

BUG=b:259716145
TEST=Kernel marks ISH (PCI device 12.0) as untrusted, and changes the
IOMMU group type to "DMA". Also, device still goes to S0i3.

Before:
$ cat /sys/devices/pci0000\:00/0000\:00\:12.0/untrusted
0
$ ls /sys/kernel/iommu_groups/5/devices
0000:00:12.0
0000:00:12.7
$ cat /sys/kernel/iommu_groups/5/type
DMA-FQ

After:
$ cat /sys/devices/pci0000\:00/0000\:00\:12.0/untrusted
1
$ ls /sys/kernel/iommu_groups/5/devices
0000:00:12.0
0000:00:12.7
$ cat /sys/kernel/iommu_groups/5/type
DMA

Change-Id: Iaddb24580bda77df0c70ff58eb098213f8b509ad
Signed-off-by: Reka Norman <rekanorman@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70633
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>
Reviewed-by: Kangheui Won <khwon@chromium.org>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
diff --git a/src/mainboard/google/brya/variants/nivviks/overridetree.cb b/src/mainboard/google/brya/variants/nivviks/overridetree.cb
index 76fe43e..f9b8430 100644
--- a/src/mainboard/google/brya/variants/nivviks/overridetree.cb
+++ b/src/mainboard/google/brya/variants/nivviks/overridetree.cb
@@ -519,6 +519,10 @@
 			probe STORAGE STORAGE_EMMC
 		end
 		device ref ish on
+			chip drivers/intel/ish
+				register "add_acpi_dma_property" = "true"
+				device generic 0 on end
+			end
 			probe STORAGE STORAGE_UFS
 		end
 		device ref ufs on