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

CONFIG_SND_OMAP_SOC_DMIC (not configurable)

modulename: snd-soc-omap-dmic.ko

configname: CONFIG_SND_OMAP_SOC_DMIC

Linux Kernel Configuration
└─>Device Drivers
└─>Sound card support
└─>Advanced Linux Sound Architecture
└─>ALSA for SoC audio support
└─>SND_OMAP_SOC_DMIC
In linux kernel since version 3.1 (release Date: 2011-10-24)  
source code:
sound/soc//omap/