[LU-12254] lnet: correct discovery event queue release

• Type: Technical task
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.13.0, Lustre 2.12.3
• Assignee: Amir Shehata (Inactive)
• Reporter: Amir Shehata (Inactive)

Description

It is possibly for events to have a ref count on the event queue when it's released in the discovery thread. When shutting down we can see an error output:

LNetError: 2770:0:(api-ni.c:1004:lnet_res_container_cleanup()) 1 active elements on exit of EQ container
LNetError: 2807:0:(module.c:655:libcfs_exit()) Portals memory leaked: 304 bytes

The eq needs to be freed after all events have been processed.