maintainers: claim responsibility for vmxnet3
maintainers: claim responsibility for vmxnet3

Signed-off-by: Yong Wang <0cd1be787884a033c98e298059e386114d22793e@vmware.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk