Changes

pelux.xml: use Qt 5.12.1 and Qt AS 5.12.1

QtAS-5.12.1 tag in meta-boot2qt is not used as it is not compatible
with thud due to LAYERSERIES_COMPAT not being set yet, therefore we are
using slightly newer revision in which it was fixed.

Signed-off-by: Oleksandr Kravchuk <oleksandr.kravchuk@pelagicore.com>

pelux.xml: bump meta-pelux

- systemd: remove network configuration
- huspell-dicts: add Czech, US English and German
- linux-raspberrypi: enable memory cgroup
- pelux.conf: set DISTRO_VERSION to master
- core-image-pelux: remove duplicate swupdate installs

Signed-off-by: Oleksandr Kravchuk <oleksandr.kravchuk@pelagicore.com>

pelux.xml: Bump meta-bistro

Changes:
    * peak-can-driver: update to 8.7.0
    * gdbus-codegen-glibmm: Fix build issue for hard-coded version

Signed-off-by: Therese Nordqvist <therese.nordqvist@pelagicore.com>

Dockerfile: update the way we fetch git-lfs

There is no version of git-lfs available by default for Ubuntu 16.04 and
the script we use to make it possible to install doesn't always succeed.
This fix means that all the commands will be run in the same context.

Signed-off-by: Therese Nordqvist <therese.nordqvist@pelagicore.com>