Bug 541294 covers migrating from smolt to lshw for inventory scanning.
One outcome of that is that the inventory task should work on aarch64 systems. This issue currently isn't expected to require additional work on the inventory task - it is included to ensure aarch64 support is specifically tested, allowing the original bug to just cover existing architectures.
The current lshw branch of beaker-system-scan works correctly.
We need to get the lshw + beaker-system-scan packages up for aarch64.
Thanks Jeff for reporting this.
I have filed a new bug 1211089 to track this.