Drop python3-eventlet from the Ubuntu Noble build Dockerfile. Clean up
remaining greenthread/greenlet terminology in comments across aiohmi
IPMI modules, consoleserver, macmap, and the IPMI plugin. Remove a
commented-out GreenPool reference in macmap.
Replace eventlet.greenpool with concurrent.futures.ThreadPoolExecutor
in the BMC discovery script, using as_completed() for proper exception
propagation and main-thread result aggregation to avoid race conditions.
Remove dead eventlet socket compatibility code (.fd attribute checks)
from the IPMI session layer, and clean up stale eventlet references
in comments across the codebase.
Closes: xcat2/confluent#197