missing move operator=

Change-Id: Id184cbc88f41eda78c58898693285e185298a1e4
Reviewed-on: https://gerrit.libreoffice.org/82343
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
diff --git a/include/cppuhelper/weakref.hxx b/include/cppuhelper/weakref.hxx
index c681284..8a94145 100644
--- a/include/cppuhelper/weakref.hxx
+++ b/include/cppuhelper/weakref.hxx
@@ -172,6 +172,12 @@ public:
            const css::uno::Reference< interface_type > & xInt )
        { WeakReferenceHelper::operator=(xInt); return *this; }

#if defined LIBO_INTERNAL_ONLY
    WeakReference & SAL_CALL operator = (
            const css::uno::Reference< interface_type > && xInt )
        { WeakReferenceHelper::operator=(std::move(xInt)); return *this; }
#endif

    /**  Gets a hard reference to the object.

         @return hard reference or null, if the weakly referenced interface has gone