CONFIG_MIGHT_HAVE_PCI is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

CONFIG_MIGHT_HAVE_PCI (not configurable)

configname: CONFIG_MIGHT_HAVE_PCI

Linux Kernel Configuration
└─>MIGHT_HAVE_PCI
In linux kernel since version 2.6.38 (release Date: 2011-03-14)  
is depended by
CONFIG_SOC_AT91RM9200