This sort of depends on what you're asking and how your company is designed.
At my company, our IT staff are the only people with the permissions to add or change hardware/software. This means that it's easy to tell anyone asking for help with this sort of thing:
I actually can't help you with that because I don't have the system permissions to do what you're asking. You'll have to talk with someone in the IT department. Here's how you contact them:...
It's also OK for you to admit that you don't know how to do it... or how it's done in your company.
I'm actually not sure what the policy is for that. I work with software design, which is really different than configuring hardware. You'll need to talk with someone in the IT department to do what you're asking. Here's how you contact them...
There's no way to feel not offended if they keep coming to you and you choose to be offended by it. That's your option. But, eventually, with enough pointers to go to IT, they'll hopefully stop coming to you first and go to IT directly. At that point, your problem is solved.
I'd like to add, there's no reason for you to feel offended by this. In fact, "feeling offended" implies that you don't respect the work that your IT staff does because you think it's below you. It's different, not necessarily "lesser". Please respect them.
I think you should reframe your reception of these people's coming to you... You said in a comment:
I would like to specify that I don't think that I'm superior, I just feel like they underestimate me, but maybe it's a personal problem.
You have it backwards: they think highly of you, so they come to you for help. People generally ask for help from people they respect, so don't think of someone asking for help as an underestimation of your abilities. Additionally, there's little reason to feel offence as the people asking you are (I would guess) simply uninformed about what a software developer/programmer does. It's just how things are. Plus, a lot of people who are developers, can to some degree, deal with hardware problems, so it's not as if the people coming to you are wrong to do so. If you don't know how to do what they're asking, it's OK to admit that.
I'm not a software developer but I do work on the system level with computers. I get requests for all sorts of hardware/software things - for example, yesterday I got asked how to add someone to an email group... I responded to the email and forwarded it... to our IT staff who deal with that thing.
Companies are big and complicated. Sometimes knowing who to talk to is confusing, so you talk to the people you know who seem like they might have your solution. I consider it a great favor to them to be able to say "I can't, but I can help figure out who can"... not everyone wants to take the time to do that, but I like to, within reason.