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

Multiplexing debug output

configname: CONFIG_OMAP_MUX_DEBUG

Linux Kernel Configuration
└─>TI OMAP1
└─>TI OMAP1 specific features
└─>Multiplexing debug output
In linux kernel since version 2.6.12  
Makes the multiplexing functions print out a lot of debug info.
This is useful if you want to find out the correct values of the
multiplexing registers.