CONFIG_SIBYTE_BCM1x80 is not available for thedefaultarchitecture x86.
Result is shown for architecture mips

CONFIG_SIBYTE_BCM1x80 (not configurable)

modulename: pci-bcm1480.ko

configname: CONFIG_SIBYTE_BCM1x80

Linux Kernel Configuration
└─>SIBYTE_BCM1x80
In linux kernel since version 2.6.15 (release Date: 2006-01-02)  
source code:
arch/mips/pci/

is selected by
CONFIG_VGA_CONSOLE