qom: Drop @errp parameter of object_property_del()

Same story as for object_property_add(): the only way
object_property_del() can fail is when the property with this name
does not exist.  Since our property names are all hardcoded, failure
is a programming error, and the appropriate way to handle it is
passing &error_abort.  Most callers do that, the commit before
previous fixed one that didn't (and got the error handling wrong), and
the two remaining exceptions ignore errors.

Drop the @errp parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-19-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
diff --git a/qom/object.c b/qom/object.c
index 23f481c..e89ffbe 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1280,15 +1280,10 @@
     return prop;
 }
 
-void object_property_del(Object *obj, const char *name, Error **errp)
+void object_property_del(Object *obj, const char *name)
 {
     ObjectProperty *prop = g_hash_table_lookup(obj->properties, name);
 
-    if (!prop) {
-        error_setg(errp, "Property '.%s' not found", name);
-        return;
-    }
-
     if (prop->release) {
         prop->release(obj, name, prop->opaque);
     }