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

ZTE specific extensions for Synopsys DW Memory Card Interface

modulename: dw_mmc-zx.ko

configname: CONFIG_MMC_DW_ZX

Linux Kernel Configuration
└─>Device Drivers
└─>MMC/SD/SDIO card support
└─>ZTE specific extensions for Synopsys DW Memory Card Interface
In linux kernel since version 4.2 (release Date: 2015-08-30)  
This selects support for ZTE SoC specific extensions to the
Synopsys DesignWare Memory Card Interface driver. Select this option
for platforms based on ZX296718 SoC's.

source code: