default or selected kernelversion does not have config value CONFIG_DVB_CINERGYT2.
Result is shown for kernelversion 5.3.7

Terratec CinergyT2/qanu USB2 DVB-T receiver

modulename: cinergyT2.ko

configname: CONFIG_DVB_CINERGYT2

Linux Kernel Configuration
└─>Device Drivers
└─>Multimedia devices
└─>DVB/ATSC adapters
└─>Terratec CinergyT2/qanu USB2 DVB-T receiver
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Support for "TerraTec CinergyT2" USB2.0 Highspeed DVB Receivers

Say Y if you own such a device and want to use it.

source code: