support/scripts: prioritize conditions for pipeline creation

support/scripts: prioritize conditions for pipeline creation

When multiple conditions match simultaneously, even though that should
not happen in practice, we want the more "important" one to win over
the less "important" ones. For example, a tag is more important than a
branch name or a trigger.

Currently, the latest condition to match takes precendence over any
previous one, while we want the exact opposite.

Fix that with proper fallbacks in else-blocks.

Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>