hw/acpi/cpu: Have build_cpus_aml() take a build_madt_cpu_fn callback

build_cpus_aml() is architecture independent but needs to create architecture-
specific CPU AML. So far this was achieved by using a virtual method from
TYPE_ACPI_DEVICE_IF. However, build_cpus_aml() would resolve this interface from
global (!) state. This makes it quite incomprehensible where this interface
comes from (TYPE_PIIX4_PM?, TYPE_ICH9_LPC_DEVICE?, TYPE_ACPI_GED_X86?) an can
lead to crashes when the generic code is ported to new architectures.

So far, build_cpus_aml() is only called in architecture-specific code -- and
only in x86. We can therefore simply pass pc_madt_cpu_entry() as callback to
build_cpus_aml(). This is the same callback that would be used through
TYPE_ACPI_DEVICE_IF.

Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230908084234.17642-3-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 2879e0d..76581d5 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -1549,8 +1549,8 @@
             .smi_path = pm->smi_on_cpuhp ? "\\_SB.PCI0.SMI0.SMIC" : NULL,
             .fw_unplugs_cpu = pm->smi_on_cpu_unplug,
         };
-        build_cpus_aml(dsdt, machine, opts, pm->cpu_hp_io_base,
-                       "\\_SB.PCI0", "\\_GPE._E02");
+        build_cpus_aml(dsdt, machine, opts, pc_madt_cpu_entry,
+                       pm->cpu_hp_io_base, "\\_SB.PCI0", "\\_GPE._E02");
     }
 
     if (pcms->memhp_io_base && nr_mem) {