tests/acpi: Add empty ACPI data files for LoongArch

Add empty acpi table for LoongArch virt machine, it is only empty
file and there is no data in these files.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Message-Id: <20250612090321.3416594-2-maobibo@loongson.cn>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

tests/qtest/bios-tables-test-allowed-diff.h

@@ -1 +1,9 @@
 /* List of comma-separated changed AML files to ignore */
+"tests/data/acpi/loongarch64/virt/APIC",
+"tests/data/acpi/loongarch64/virt/DSDT",
+"tests/data/acpi/loongarch64/virt/FACP",
+"tests/data/acpi/loongarch64/virt/MCFG",
+"tests/data/acpi/loongarch64/virt/PPTT",
+"tests/data/acpi/loongarch64/virt/SLIT",
+"tests/data/acpi/loongarch64/virt/SPCR",
+"tests/data/acpi/loongarch64/virt/SRAT",