Comment 2 for bug 468119

The module must not be removed. Microcode updates are ephemeral and will be lost should your computer need to reset the processor for any reason (typical ones are: new core being brought online, suspend to RAM, suspend to disk).

If none of these situations apply to you, you can remove the module at your own risk, for very little gain and bearing the cost of a full kernel stop while the module is unloaded. But it is not something that can be safely done as a rule, it is something you will have to configure in your own system.