i915 update failed on upgrade to 1.157.4

[Andriy Tymchenko]

During apt upgrade to version 1.157.4, I got initramfs update failure

Setting up linux-firmware (1.157.4) ...
Setting up linux-libc-dev:amd64 (4.4.0-42.62) ...
Setting up network-manager (1.2.2-0ubuntu0.16.04.3) ...
Processing triggers for initramfs-tools (0.122ubuntu8.3) ...
update-initramfs: Generating /boot/initrd.img-4.4.0-38-generic
W: Possible missing firmware /lib/firmware/i915/kbl_dmc_ver1.bin for module i915_bpo
W: Possible missing firmware /lib/firmware/i915/skl_guc_ver6.bin for module i915_bpo
Compiling platform/gsutil/third_party/httplib2/python3/httplib2/__init__.py ...
  File "platform/gsutil/third_party/httplib2/python3/httplib2/__init__.py", line 347
    print('%s:' % h, end=' ', file=self._fp)
                        ^
SyntaxError: invalid syntax
-----------------

After upgrade has passed, files mentioned above had been not present

ll /lib/firmware/i915/

total 340
drwxr-xr-x 2 root root 4096 Oct 16 19:35 ./
drwxr-xr-x 74 root root 32768 Oct 16 19:35 ../
-rw-r--r-- 1 root root 5872 Sep 14 16:15 bxt_dmc_ver1_04.bin
-rw-r--r-- 1 root root 5872 Sep 14 16:15 bxt_dmc_ver1_05.bin
-rw-r--r-- 1 root root 8380 Sep 14 16:15 bxt_dmc_ver1_06.bin
-rw-r--r-- 1 root root 8380 Aug 15 17:40 bxt_dmc_ver1_07.bin
lrwxrwxrwx 1 root root 19 Aug 15 17:40 bxt_dmc_ver1.bin -> bxt_dmc_ver1_07.bin
-rw-r--r-- 1 root root 8824 Sep 14 15:47 skl_dmc_ver1_23.bin
-rw-r--r-- 1 root root 8928 Jul 12 22:33 skl_dmc_ver1_26.bin
lrwxrwxrwx 1 root root 19 Jul 12 22:33 skl_dmc_ver1.bin -> skl_dmc_ver1_26.bin
-rw-r--r-- 1 root root 109636 Sep 14 16:15 skl_guc_ver1_1059.bin
lrwxrwxrwx 1 root root 21 Sep 14 16:15 skl_guc_ver1.bin -> skl_guc_ver1_1059.bin
-rw-r--r-- 1 root root 128320 Sep 14 16:15 skl_guc_ver4_3.bin
lrwxrwxrwx 1 root root 18 Sep 14 16:15 skl_guc_ver4.bin -> skl_guc_ver4_3.bin

-----------------

Manual update for initramfs causes error mesage too

sudo update-initramfs -u

update-initramfs: Generating /boot/initrd.img-4.4.0-38-generic
W: Possible missing firmware /lib/firmware/i915/kbl_dmc_ver1.bin for module i915_bpo
W: Possible missing firmware /lib/firmware/i915/skl_guc_ver6.bin for module i915_bpo
------------------

lsb_release -a

No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04.1 LTS
Release: 16.04
Codename: xenial

-------------------

apt-cache policy linux-firmware

linux-firmware:
  Installed: 1.157.4
  Candidate: 1.157.4
  Version table:
 *** 1.157.4 500
        500 http://fi.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
        500 http://fi.archive.ubuntu.com/ubuntu xenial-updates/main i386 Packages
        100 /var/lib/dpkg/status
     1.157 500
        500 http://fi.archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        500 http://fi.archive.ubuntu.com/ubuntu xenial/main i386 Packages

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Timo Aaltonen (tjaalton)]

that's not an error but a warning