This interface is implemented by the Xtensa core which holds the
configuration of the Windowed Watchdog Timer. The device itself is not part
of the core, but implemented as an external device which fetches these
values for correct device simulation, making the wwdt device generic
for all configurations.
The has_wwdt method reports if the wwdt option is included in the
core at all. The rest of the member functions extract configuration details
from the core, if the core does not have wwdt enabled, all are zeros.