default or selected kernelversion does not have config value CONFIG_IP_ROUTE_MULTIPATH_CACHED.
Result is shown for kernelversion 5.4.123

IP: equal cost multipath with caching support (EXPERIMENTAL)

modulename: multipath.ko

configname: CONFIG_IP_ROUTE_MULTIPATH_CACHED

Linux Kernel Configuration
└─>Networking support
└─>Networking options
└─>IP: equal cost multipath with caching support (EXPERIMENTAL)
In linux kernel since version 2.6.12  
Normally, equal cost multipath routing is not supported by the
routing cache. If you say Y here, alternative routes are cached
and on cache lookup a route is chosen in a configurable fashion.

If unsure, say N.

source code: