default or selected kernelversion does not have config value CONFIG_HAVE_MMU_GATHER_PAGE_SIZE.
Result is shown for kernelversion 6.9.8

CONFIG_HAVE_MMU_GATHER_PAGE_SIZE (not configurable)

configname: CONFIG_HAVE_MMU_GATHER_PAGE_SIZE

Linux Kernel Configuration
└─>General architecture-dependent options
└─>HAVE_MMU_GATHER_PAGE_SIZE
In linux kernel since version 5.2 (release Date: 2019-07-07)