Hi,
The PC peer link can be configured on M1 series I/O modules, but only on the 10GE modules. From the Configuring vPC section of the Nexus 7000 configuration guide:
vPC Peer Links
A vPC peer link is the link that is used to synchronize the states between the vPC peer devices. Both ends of the link must be on 10-Gigabit Ethernet interfaces.
What type are your M1 I/O modules? I can't see from what you attached.
Regards