Improve network discovery event condition evaluation performance

Currently event processing is done for each IP, this results in transaction count being equal to IP count and after ZBXNEXT-3588 events are evaluated in single query per condition, so this has improved to query count being equal to IP * conditions from IP * conditions * events. However this can be further improved by evaluating multiple IP in bulk (process events after all IP addresses are processed, not in between each IP), thus decreasing query count to condition count instead of IP count.

Performance tests should be done with evaluating conditions for many IP addresses when using discovery and required changes should be implemented.