ACPICA: iasl: Fix IORT SMMU GSI disassembling

ACPICA commit 637b88de24a78c20478728d9d66632b06fcaa5bf

If the IORT template is compiled and then iort.aml binary disassembled to
iort.dsl, SMMUv1 node lists incorrect offset for SMMU_Nsg_cfg_irpt Interrupt:
[0ECh 0236   8]       SMMU_Nsg_irpt Interrupt : 0000000000000000
[0ECh 0236   8]    SMMU_Nsg_cfg_irpt Interrupt : 0000000000000000
This is because iasl hasn't implemented SMMU GSI decoding yet.

This patch fixes this issue by preparing structures for decoding IORT SMMU
GSI. ACPICA BZ 1340, reported by Alexei Fedorov, fixed by Lv Zheng.

Link: https://github.com/acpica/acpica/commit/637b88de
Link: https://bugs.acpica.org/show_bug.cgi?id=1340


Reported-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>