The value of tmnxCcIpFltrSourceIpMask specifies the IP Mask value for
this policy IP Filter entry. The mask is ANDed with the received Source
IP address to match the tmnxCcIpFltrSourceIpAddr.
The default value of 0 disables matching on the Source IP address.
This field can only be set if the value of tmnxCcIpFltrDirection is set
to egress.