Hi Nishant, and Harish,
SRIOVNicSwitch mechanism driver enable the basic SRIOV capabilities inbox. the SRIOVNicSwitch agent enable capability of disable /enable the VF to a NIC that supports it (like connectX).
the Mech_mlnx mechanism driver of Mellanox is still available to support infiniband SRIOV capabilities.
BTW - in Kilo, all vendor plugins will be extract from neutron core to an external (stackforge) repository.
Nurit