kernelconfig_penguin
default or selected kernelversion does not have config value CONFIG_NETLINK_MMAP.
Result is shown for kernelversion 6.5.1
depends
CONFIG_NET

NETLINK: mmaped IO

configname: CONFIG_NETLINK_MMAP

Linux Kernel Configuration
└─> Networking support
└─> Networking options
└─> NETLINK: mmaped IO

In linux kernel since version 3.1 (release Date: 2011-10-24)  

This option enables support for memory mapped netlink IO. This
reduces overhead by avoiding copying data between kernel- and
userspace.

If unsure, say N.