CONFIG_USB_NET_CDC_SUBSET_ENABLE (not configurable)

modulename: cdc_subset.ko

configname: CONFIG_USB_NET_CDC_SUBSET_ENABLE

Linux Kernel Configuration
└─>Device Drivers
└─>Network device support
└─>USB Network Adapters
└─>USB_NET_CDC_SUBSET_ENABLE
In linux kernel since version 4.1 (release Date: 2015-06-21)  
source code:
drivers/net/usb/cdc_subset.c