It's a lie like so much other stuff in the press. I'm currently in Turkey/Antalya, I've a cell-phone with a turkish Vodafone SIM card - I had several phone calls today - no president in my phone.
But I guess, the BTK guy, went too far to put the 10sec celebration message of the president to celebrate the official national public holiday. Just FYI - on prepaid tariffs there's already some kind of ads by mobile operators.