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

Generic OMAP board

modulename: board-generic.ko

configname: CONFIG_MACH_OMAP_GENERIC

Linux Kernel Configuration
└─>TI OMAP1 specific features
└─>Generic OMAP board
In linux kernel since version 2.6.12  
Support for generic OMAP-1510, 1610 or 1710 board with
no FPGA. Can be used as template for porting Linux to
custom OMAP boards. Say Y here if you have a custom
board.

source code: