Fix fg and bg packages orders in the checker

This commit fixes the order for the foreground and background packages during the checks.

It implements the following checks, where the first image type belong to the foreground packages, and the rest are the background packages:

• target: for packages to be installed on minimal images
• target + development: for packages to be installed on target images
• development + target: for tools used by OBS and developers
• hmi + target + development: for HMI packages to be installed on target images
• sdk + target + development: for packages to be installed on basesdk images
• sdk + target+ development + hmi: for packages to be installed on sdk images

Signed-off-by: Luis Araujo luis.araujo@collabora.co.uk