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

ChromeOS Embedded Controller LPC Microchip EC (MEC) variant

configname: CONFIG_CROS_EC_LPC_MEC

Linux Kernel Configuration
└─>Device Drivers
└─>Platform support for Chrome hardware
└─>ChromeOS Embedded Controller LPC Microchip EC (MEC) variant
In linux kernel since version 4.2 (release Date: 2015-08-30)  
If you say Y here, a variant LPC protocol for the Microchip EC
will be used. Note that this variant is not backward compatible
with non-Microchip ECs.

If you have a ChromeOS Embedded Controller Microchip EC variant
choose Y here.