mb/google/brya/var/marasov: Add _DSD object for wifi

`is_untrusted` is eventually ended up by adding DMA property _DSD which is similar to what `add_acpi_dma_property` does for WWAN drivers,
hence it makes sense to have a unified name across different device drivers.

BUG=b:278310435
BRANCH=firmware-brya-14505.B
TEST=Verified that the _DSD object is still present in the SSDT.

Signed-off-by: Frank Chu <Frank_Chu@pegatron.corp-partner.google.com>
Change-Id: I5a69a47e67f6acaad5a5d1b67e437c5a41bebf3e
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74499
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Reviewed-by: Frank Chu <frank_chu@pegatron.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/brya/variants/marasov/overridetree.cb

@@ -290,6 +290,7 @@ chip soc/intel/alderlake
 				.flags = PCIE_RP_LTR | PCIE_RP_AER,
 			}"
 			chip drivers/wifi/generic
+				register "add_acpi_dma_property" = "true"
 				device pci 00.0 on end
 			end
 		end