256k vmembers for IRB and aggregated Ethernet interfaces

Increases number of vmembers to 256k for integrated routing and bridging interfaces and aggregated Ethernet interfaces. To calculate how many interfaces are required to support 4,000 VLANs, for example, divide the maximum number of vmembers (256,000) by the number of configured VLANs (4,000). In this case, 64 interfaces are required.