default or selected kernelversion does not have config value CONFIG_ISDN_DRV_AVMB1_B1PCIV4.
Result is shown for kernelversion 6.9.9

AVM B1 PCI V4 support

configname: CONFIG_ISDN_DRV_AVMB1_B1PCIV4

Linux Kernel Configuration
└─>Device Drivers
└─>ISDN support
└─>CAPI 2.0 subsystem
└─>Active AVM cards
└─>AVM B1 PCI V4 support
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Enable support for the V4 version of AVM B1 PCI card.