calling IsSet() before Call() on Link<> is unnecessary

the Call() already does a check

Found with:
git grep -A 1 -w 'IsSet()'
    | grep -B 1 '.Call('
    | grep ':'
    | cut -d ':' -f 1

Change-Id: Ia7248f5d62640b75f705e539c3d1183e39c0d847

extensions/source/propctrlr/sqlcommanddesign.cxx

@@ -309,8 +309,7 @@ namespace pcr
 
     void SQLCommandDesigner::impl_designerClosed_nothrow()
     {
-        if ( m_aCloseLink.IsSet() )
-            m_aCloseLink.Call( *this );
+        m_aCloseLink.Call( *this );
     }