feature to enable cdp/lldp on leaf/spine feature is available now from 4.2(1i) onwards...please follow below document for configuration. https://www.cisco.com/c/en/us/td/docs/switches/datacenter/aci/apic/sw/kb/b_APIC_CDP_and_LLDP_Management_Interface...

Leaf101# show int po7port-channel7 is down (epm-learn-err-disable)   disable and enable port-channel 7 on leaf, solved the issue.    Leaf101# show interface port-channel 7 status------------------------------------------------------------------------...