default or selected kernelversion does not have config value CONFIG_OKTAGON_SCSI.
Result is shown for kernelversion 5.15.113

BSC Oktagon SCSI support (EXPERIMENTAL)

modulename: NCR53C9x.ko

configname: CONFIG_OKTAGON_SCSI

Linux Kernel Configuration
└─>Device Drivers
└─>SCSI device support
└─>SCSI low-level drivers
└─>BSC Oktagon SCSI support (EXPERIMENTAL)
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
If you have the BSC Oktagon SCSI disk controller for the Amiga, say
Y to this question. If you're in doubt about whether you have one,
see the picture at
<http://amiga.resource.cx/exp/search.pl?product=oktagon>.

source code:
depends
CONFIG_EXPERIMENTAL
CONFIG_SCSI
CONFIG_ZORRO