ACPICA: iASL: Decode subtable type field for VIOT

For the table disassembler, decode the subtable type field to a descriptive string.

ACPICA commit 2197e354fb5dcafaddd2016ffeb0620e5bc3d5e2

Link: https://github.com/acpica/acpica/commit/2197e354


Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Erik Kaneda <erik.kaneda@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>