My recommendation would be to download the Schematic files for Freescale’s Reference Boards, opening the Schematics and then exporting the processor symbol. It might not be very straightforward but there is no symbol library available on Freescale’s website.
The symbol would be the same for all i.MX6Q processors as the differences between part numbers are related to temperature, certification or clock frequency, so you should be covered using the symbol from the i.MX&Q SABRE Board.
