CONFIG_BF549_std is not available for thedefaultarchitecture x86.
Result is shown for architecture blackfin
default or selected kernelversion does not have config value CONFIG_BF549_std.
Result is shown for kernelversion 6.7-rc3

BF549

configname: CONFIG_BF549_std

CPU
└─>BF549
In linux kernel since version 2.6.33 (release Date: 2010-02-24)  
BF549 Processor Support.