acpi: applesmc: use AcpiDevAmlIfClass:build_dev_aml to provide device's AML

acpi: applesmc: use AcpiDevAmlIfClass:build_dev_aml to provide device's AML

  .. and clean up not longer needed conditionals in DSTD build
code. applesmc AML will be fetched and included when ISA bridge
will build its own AML code (incl. attached devices).

Expected AML change:
the device under separate _SB.PCI0.ISA scope is moved directly
under Device(ISA) node.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Message-Id: <20220608135340.3304695-25-imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>