While there is no scripts to perform the migration, there are some simularities with A10's aRules and our iRules last I viewed them. This should make any iRules that need to be migrated done with minimal effort.
Whenever migrating from one platform to another, it is recommended to start from fresh and build the new configuration using our LTM Operations guide found here.
It is going to be a manual process for the most part unless you know how to use sed, awk and grep in linux. If so you can pull most of the data you need from the A10 config file then use that to build your configuation.
Alternatively we have a Professional Services team that can assist with that migration.
https://www.f5.com/services/professional-services