CONFIG_CSRC_SB1250 is not available for thedefaultarchitecture x86.
Result is shown for architecture mips

CONFIG_CSRC_SB1250 (not configurable)

modulename: csrc-sb1250.ko

configname: CONFIG_CSRC_SB1250

Linux Kernel Configuration
└─>CSRC_SB1250
In linux kernel since version 2.6.24 (release Date: 2008-01-24)  
source code:
arch/mips/kernel/csrc-sb1250.c