CONFIG_MACH_OMAP_2430SDP is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

OMAP 2430 SDP board

modulename: board-2430sdp.ko

configname: CONFIG_MACH_OMAP_2430SDP

Linux Kernel Configuration
└─>OMAP 2430 SDP board
In linux kernel since version 2.6.24 (release Date: 2008-01-24)  
source code:
/arch/arm/mach-omap2/