acpi: simplify _OSC

Our _OSC method has a bunch of unused code loading data
into external CTRL and SUPP fields which are then never
used. Drop this in favor of a single local variable.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>

hw/i386/acpi-build.c

@@ -1804,7 +1804,7 @@ static Aml *build_q35_osc_method(void)
     Aml *else_ctx;
     Aml *method;
     Aml *a_cwd1 = aml_name("CDW1");
-    Aml *a_ctrl = aml_name("CTRL");
+    Aml *a_ctrl = aml_local(0);
 
     method = aml_method("_OSC", 4, AML_NOTSERIALIZED);
     aml_append(method, aml_create_dword_field(aml_arg(3), aml_int(0), "CDW1"));
@@ -1814,7 +1814,6 @@ static Aml *build_q35_osc_method(void)
     aml_append(if_ctx, aml_create_dword_field(aml_arg(3), aml_int(4), "CDW2"));
     aml_append(if_ctx, aml_create_dword_field(aml_arg(3), aml_int(8), "CDW3"));
 
-    aml_append(if_ctx, aml_store(aml_name("CDW2"), aml_name("SUPP")));
     aml_append(if_ctx, aml_store(aml_name("CDW3"), a_ctrl));
 
     /*
@@ -1899,8 +1898,6 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
         aml_append(dev, aml_name_decl("_CID", aml_eisaid("PNP0A03")));
         aml_append(dev, aml_name_decl("_ADR", aml_int(0)));
         aml_append(dev, aml_name_decl("_UID", aml_int(1)));
-        aml_append(dev, aml_name_decl("SUPP", aml_int(0)));
-        aml_append(dev, aml_name_decl("CTRL", aml_int(0)));
         aml_append(dev, build_q35_osc_method());
         aml_append(sb_scope, dev);
         aml_append(dsdt, sb_scope);