Add a default value to ObjectProperty and an implementation of
ObjectPropertyInit that uses it. This will make it easier to show the
default in help messages.
Also provide convenience functions object_property_set_default_{bool,
str, int, uint}().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20200110153039.1379601-11-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>