This object indicates the forced switching flag.
Forced switching, as described in G.781, is used to
override the currently selected synchronization source,
The T4 selected synchronization source is identified by
cnsExtOutSelNetsyncIndex, which contains the index to
the clock source in cnsT4ClockSourceTable.
The 'true' value indicates the currently selected
T4 clock source is a result of the forced switching.
The 'false' value indicates the currently selected T4
clock source is not a result of forced switching.