update-initramfs: Generating /boot/initrd.img-4.4.0-15-generic
W: Possible missing firmware /lib/firmware/radeon/TAHITI_vce.bin for module radeon
W: Possible missing firmware /lib/firmware/i915/bxt_dmc_ver1.bin for module i915
W: Possible missing firmware /lib/firmware/i915/skl_guc_ver4.bin for module i915