Saddam gave Turkey the legal right to do that in the 90s because Iraq was unable to cause of the no fly zones by NATO and the coalition.
Today is different, today the Turkish gov is violating the constitution of the central government, meddling in internal affairs, therefor they respond with these kind of things.
Iraq being hostile to Turkey is the wrong way your viewing it, would you accept it if Iran ships heavy weapons to the PKK ? or meddling in internal Turkish affairs ?Besides the country has the right to arm itself, its not our fault this would hurt imperial dreams of others..