I've worked in places where this would be a problem, and others where it was expected that the coffees get made as first order of the day.
Some organisations have issues with staff logging on THEN making a drink as once logged on you are on paid company time, and your first act is to go make yourself a drink instead of starting the work you are paid to do. This is most important in an environment where logging in time is recorded, because then you are taking the piss a bit.
Most companies with start times or set hours expect employees to be at their desk ready to start work at a certain time or at log in point - you aren't doing that. You're logging in before you are ready to start work then wandering off.
It depends on the ethos and rules of your workplace, in some I've worked in you would be told in no uncertain terms, by management, to pack it in. As someone has mentioned it you should listen.
Make your coffee before logging on - and if that isn't possible because you haven't time before you are meant to be logged on that's your evidence that you were taking the piss. If you have to arrive five minutes earlier or leave five minutes later to facilitate making a coffee before log on - ditto.
If it makes no difference to any of the above then it won't make any difference to you anyway. But it probably does, in which case you have been out of order.