Building a kernel test produced an error about a missing config
apparently because of recent changes in the run tool. So, we add
a dummy XML node as config.
Ref #1972
The run test 'hw_info' prints the content of the basic ARMv7 identification and
feature registers in a pretty readable format. It is a kernel-internal test
because many of these registers are restricted to privilege level 1 or higher.
fix#1278