default or selected kernelversion does not have config value CONFIG_ARM_AM79C961A.
Result is shown for kernelversion 5.9.9

ARM EBSA110 AM79C961A support

modulename: am79c961a.ko
configname: CONFIG_ARM_AM79C961A

Linux Kernel Configuration
└─> Device Drivers
└─> Network device support
└─> Ethernet driver support
└─> ARM EBSA110 AM79C961A support

If you wish to compile a kernel for the EBSA-110, then you should
always answer Y to this.

source code: