Don't create user homedir in the image build

Depending on how Apertis images are deployed (e.g. ostree, lxc or
debian) at first boot there may or may not be a home directory for the
user anymore. To make things more consistent simply never create the
users home directory at image build time, which means in all image types
the users homedirectory should be created at first boot.

As a bonus this avoids the ostree commits containing a homedir which
will get mounted over.

Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>

scripts/setup_user.sh

@@ -3,7 +3,7 @@
 set -e
 
 echo "I: create user"
-adduser --gecos User --disabled-login user
+adduser --gecos User --no-create-home --disabled-login user
 
 echo "I: set user password"
 echo "user:user" | chpasswd