When clicking on the "Add As Friend" button it changes to "Awaiting Approval". It's obviously waiting for approval from the other party, but unless the request is accepted, it's waiting forever.
I suppose it's not a big deal, but I see no compelling reason why the software would now allow to cancel such a request. Perhaps you clicked by accident or change your mind. This should easily be accomplished by clicking on the "Awaiting Approval" button, which should then rather be named "Cancel Request".