Improve logic for 01_elemental-rootfs.yaml

[mjura]

Every time when we want to write configurarion file in /usr/loca/etc
directory has to be checked and created properly.

Otherwise we will see

Running stage: initramfs
Executing /system/oem/01_elemental-rootfs.yaml
Applying 'Elemental Rootfs Layout Settings' for stage 'initramfs'. Total stages: 3
Processing stage step ''. ( commands: 1, files: 0, ... )
Command output: sh: line 1: /usr/local/etc/hostname: No such file or directory
Processing stage step 'Persist /etc/machine-id'. ( commands: 1, files: 0, ... )
Command output:
Processing stage step 'Create essential persistent paths'. ( commands: 0, files: >

Signed-off-by: Michal Jura mjura@suse.com

[davidcassany]

Looks good 👍