linux/arm-smccc.h is included more than once, Remove the one that isn't
necessary.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://lore.kernel.org/r/1599643682-10404-1-git-send-email-tiantao6@hisilicon.com


Signed-off-by: Will Deacon <will@kernel.org>