To do this in the Alarm panel, Trap Management, Filtering Trap. Add a new filter, name, select common trap, up/down trap and then select all the ethernet ports of the devices your not interested in getting alarms about, select all days and all times.
This is now filtered out for those selected ports, its easier than going to each switch individually and disabling the trap.
To filter the traps, you can follow the summary rafter gave to have IMC filter the alarms for non-interested ports or all ports.
To impact the poll alarms... System-->System Configuration-->System Settings - interface up/down alarm filters. From there you can chose to filter disconnected links, PC connected, server connected... I usually filter everything other than server connected links.
The other spot to do some fine-tuning, is under resource -->batch operations-->interface up/down alarm filter. From there you can select whatever ports you want from whatever devices, and chose to filter/not filter them, or keep the system settings described above).
Please use admin guide for configuration : https://support.hpe.com/hpsc/doc/public/display?sp4ts.oid=1010494621&docLocale=en_US&docId=emr_na-c05367532