target-xtensa: Introduce QOM realizefn for XtensaCPU

Introduce realizefn and set realized = true in cpu_xtensa_init().

Signed-off-by: Andreas Färber <afaerber@suse.de>
diff --git a/target-xtensa/helper.c b/target-xtensa/helper.c
index 94c03a1..14bcc7e 100644
--- a/target-xtensa/helper.c
+++ b/target-xtensa/helper.c
@@ -104,7 +104,9 @@
     }
 
     xtensa_irq_init(env);
-    qemu_init_vcpu(env);
+
+    object_property_set_bool(OBJECT(cpu), true, "realized", NULL);
+
     return cpu;
 }