CONFIG_SIBYTE_UNK_BCM1250 is not available for thedefaultarchitecture x86.
Result is shown for architecture mips
default or selected kernelversion does not have config value CONFIG_SIBYTE_UNK_BCM1250.
Result is shown for kernelversion 5.4.123
BCM1250
configname: CONFIG_SIBYTE_UNK_BCM1250
BCM1xxx SOC Type
└─>BCM1250