The value of the partner initial receive pacing window. This
is our initial send pacing window for all new circuits on this
transport connection, as modified and granted by the first flow
control indication the partner sends on each circuit.
This information is obtained from a DLSw capabilities exchange
message received from the partner DLSw.
A value of zero is returned before a Capabilities
Exchange message is received, or if one is never received.
If an implementation chooses to keep ciscoDlswTConnOperEntrys in
the `disconnected' state, this value should remain unchanged.