watchdog: Rename timer use fields and enum

The name of the num should not contain the word Field as the type is not
a field, just the use case for the timer.

The properties on the watchdog object should be clear as to being the
current or last expired timer use.

Change-Id: Iee21fbfa97e5ef0634b3f806a43d7d3e66288661
Signed-off-by: William A. Kennington III <wak@google.com>
1 file changed