Why don't I have the option to select a link common clock in the Qsys IP compiler for PCI express core?

Description

It is not possible to select the "Link Common Clock" option for the IP compiler for PCI express core during customization in Qsys.  This is due to the option being omitted from the peripheral configuration GUI.

This issue is addressed in the Quartus® II software version 11.1 Service Pack 2.