iavf: Refactor the watchdog state machine

Refactor the watchdog state machine implementation.
Add the additional state __IAVF_COMM_FAILED to process
the PF communication fails. Prepare the watchdog state machine
to integrate with init state machine.

Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Signed-off-by: Jakub Pawlak <jakub.pawlak@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>