LoongArch: fix percpu area not allocated as expected

LoongArch inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7PT2H



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Percpu area not allocated as expected because some CONFIG not defined,
Defined the required CONFIG to fix it.

Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>