I have the same messages in Ubunty Zesty:
update-initramfs: Generating /boot/initrd.img-4.9.0-6-generic
W: Possible missing firmware /lib/firmware/i915/kbl_guc_ver9_14.bin for module i915
W: Possible missing firmware /lib/firmware/i915/bxt_guc_ver8_7.bin for module i915
I have the same messages in Ubunty Zesty: img-4.9. 0-6-generic i915/kbl_ guc_ver9_ 14.bin for module i915 i915/bxt_ guc_ver8_ 7.bin for module i915
update-initramfs: Generating /boot/initrd.
W: Possible missing firmware /lib/firmware/
W: Possible missing firmware /lib/firmware/