I don't know what or who added this file but omv-extras did not add it. You need to either change the reference to jessie to stretch (no idea if this works) or remove this file.
Disable the hwraid repo in omv-extras. There is no plugins in it.
I haven't tried it and I don't have hardware to test. Can you install it? Maybe.
in order to answer:
I use wheezy (sample on HP forum), then jessie (as you said, or as i think you meaned), and stretch (to test) and it's ok. i have this for HP tools (HW management from ssh/cli), like ssacli and hpacucli
i disable HWraid for the moment, it creates error message when update management.
i don't know how i can install this HPraid plugin. if you have an idea...
thanks for your help
I think after this test and experience with this 1st NAS, i m going to upgrade the others... and disable omv-extras/hwraid. very sad, because, all of my nas have hw raid card, and also sw raid too.