xen/arm: smmuv3: Change *array into *const array

xen/arm: smmuv3: Change *array into *const array

Backport Linux commit d56d5162e317. This is the clean backport without
any changes.

Fix checkpatch warning in arm-smmu-v3.c:
static const char * array should probably be static const char
* const

Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>
Origin: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git d56d5162e317
Signed-off-by: Rahul Singh <rahul.singh@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>