default or selected kernelversion does not have config value CONFIG_MTD_RPXLITE.
Result is shown for kernelversion 6.2.5

CFI Flash device mapped on RPX Lite or CLLF

modulename: rpxlite.ko

configname: CONFIG_MTD_RPXLITE

Linux Kernel Configuration
└─>Device Drivers
└─>Memory Technology Device (MTD) support
└─>Mapping drivers for chip access
└─>CFI Flash device mapped on RPX Lite or CLLF
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
The RPXLite PowerPC board has CFI-compliant chips mapped in
a strange sparse mapping. This 'mapping' driver supports that
arrangement, allowing the CFI probe and command set driver code
to communicate with the chips on the RPXLite board. More at
<http://www.embeddedplanet.com/>.

source code:
depends
CONFIG_MTD
CONFIG_MTD_CFI
CONFIG_RPXCLASSIC or CONFIG_RPXLITE