This object allows user to specify what this port should do
if it receives a flow control request.
This object is ignored when nbsCmmcPortFlowControl is
disabled.
If this object reports notSupported(1), no changes to this
object are allowed.
Setting this object to drop(2) indicates that this port
should ignore requests to control its flow.
Setting this object to comply(3) means this port should
grant flow control requests from the connected port, and
buffer up traffic while the other side catches up.
If this object is set to passthru(4), the port will not
comply with the request, but will relay it along to the next
port.
The corresponding nbsCmmcPortFCRecvOper object indicates
the setting that is actually in effect.