default or selected kernelversion does not have config value CONFIG_INPUT_OF_MATRIX_KEYMAP.
Result is shown for kernelversion 5.3.7

CONFIG_INPUT_OF_MATRIX_KEYMAP (not configurable)

modulename: of_keymap.ko

configname: CONFIG_INPUT_OF_MATRIX_KEYMAP

Linux Kernel Configuration
└─>Device Drivers
└─>Input device support
└─>INPUT_OF_MATRIX_KEYMAP
In linux kernel since version 3.4 (release Date: 2012-05-20)  
source code:
drivers/input/of_keymap.c

is depended by
CONFIG_KEYBOARD_TEGRA