Hi Andy,
Intel Firmware Descriptor is a 4KB big binary structure that describes the layout of the SPI flash in the Intel firmware. Besides the layout it contains various straps for CPU and chipset configuration which is sampled at power-on.
There is nothing to worry about the lack of IFD. You may still flash the coreboot on your laptop, but you have to remember to leave the IFD region (and ME region too) untouched. If you are using flashrom, you should pass the "--ifd -i bios" options to the flashrom command when flashing. It will instruct flashrom to overwrite the BIOS region only in flash, where coreboot is supposed to be placed.
You may always extract the IFD for the original firmware of your laptop and include it in your coreboot build. Creating own IFD is not recommended.
Best regards,