Build devroots and preinstall them into SDK images

See https://phabricator.apertis.org/T5423.

added 8 commits

• b2cd901a - 1 commit from branch master
• fbdcde1d - Split apertis-ospack.yaml into separate recipes
• 289e608f - Split/rename the development sysroot recipe into sysroot/devroot
• 6aafec03 - Pass the suite name to the image recipes
• 8ed0929f - Move the common URL part into image_url_prefix
• 2357287c - Pass timestamp to image building recipes
• 6ab1fa48 - Pass the imageroot URL to the image recipes
• 3e7f591f - Preinstall the devroot into the SDK images

Compare with previous version

merged