ARM: dts: hisilicon: use the correct HiSilicon copyright

s/Hisilicon/HiSilicon/.
It should use capital S, according to the official website
https://www.hisilicon.com/en

.

Signed-off-by: Hao Fang <fanghao11@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>