CONFIG_MB_MANAGER is not available for thedefaultarchitecture x86.
Result is shown for architecture microblaze

Support for Microblaze Manager

configname: CONFIG_MB_MANAGER

Linux Kernel Configuration
└─>Kernel features
└─>Support for Microblaze Manager
In linux kernel since version 6.1 (release Date: 2022-12-11)  
This option enables API for configuring the MicroBlaze manager
control register, which is consumed by the break handler to
block the break.

Say N here unless you know what you are doing.