default or selected kernelversion does not have config value CONFIG_SOC_TEGRA_PMC_TEGRA186.
Result is shown for kernelversion 6.7-rc3

CONFIG_SOC_TEGRA_PMC_TEGRA186 (not configurable)

modulename: pmc-tegra186.ko

configname: CONFIG_SOC_TEGRA_PMC_TEGRA186

Linux Kernel Configuration
└─>Device Drivers
└─>SOC (System On Chip) specific Drivers
└─>SOC_TEGRA_PMC_TEGRA186
In linux kernel since version 4.7.2 (release Date: 2016-08-20)  
source code:
drivers/soc/tegra/pmc-tegra186.c