CONFIG_BOARD_MRMT_AC97 is not available for thedefaultarchitecture x86.
Result is shown for architecture avr32
default or selected kernelversion does not have config value CONFIG_BOARD_MRMT_AC97.
Result is shown for kernelversion 6.5.1

Enable AC97 CODEC

configname: CONFIG_BOARD_MRMT_AC97

Linux Kernel Configuration
└─>Enable AC97 CODEC
In linux kernel since version 2.6.31 (release Date: 2009-09-09)  
Enable the UCB1400 AC97 CODEC driver.