irqchip: add sw64 chip3 builtin LPC interrupt controller driver

Sunway inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5G7AK



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This adds an irqchip driver for the secondary interrupt controllers
based on sw64 chip3 cpu builtin LPC.

Signed-off-by: Zhu Donghong <zhudonghong@wxiat.com>

Signed-off-by: Gu Zitao <guzitao@wxiat.com>