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

CONFIG_DEFAULT_SGI_PARTITION (not configurable)

configname: CONFIG_DEFAULT_SGI_PARTITION

Linux Kernel Configuration
└─>DEFAULT_SGI_PARTITION
In linux kernel since version 2.6.25 (release Date: 2008-04-16)  
is depended by
CONFIG_SGI_IP28