x86: config: Increase maximum number of CPUs to 512

[Avenger-285714]

The default number is 64.
At a cloud environment, you may be assigned 128 or more CPUs so that 64 is not enough.

Reported-by: Zhao Ou [email protected]

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关键摘要:

• 在CONFIG_NR_CPUS配置项后新增了一个值，但未提供上下文说明为什么需要设置这个特定的值。
• 检查CONFIG_NR_CPUS=512是否与系统架构和硬件兼容，避免潜在的配置错误。

是否建议立即修改:

• 是，建议添加必要的注释来解释CONFIG_NR_CPUS=512的用途和原因，以便其他开发者理解这一变更。
• 是，需要确认新增的配置项值512是否与系统架构和硬件兼容，避免潜在的配置错误。