default or selected kernelversion does not have config value CONFIG_SND_SOC_NUC900EVB.
Result is shown for kernelversion 6.9.9

NUC900 AC97 support for demo board

modulename: snd-soc-nuc900-audio.ko

configname: CONFIG_SND_SOC_NUC900EVB

Linux Kernel Configuration
└─>Device Drivers
└─>Sound card support
└─>Advanced Linux Sound Architecture
└─>ALSA for SoC audio support
└─>NUC900 AC97 support for demo board
In linux kernel since version 2.6.36 (release Date: 2010-10-20)  
Select this option to enable audio (AC97) on the
NUC900 demoboard.

source code:
sound/soc//nuc900/