iommu/arm-smmu-v3: Fix l1 stream table size in the error message

iommu/arm-smmu-v3: Fix l1 stream table size in the error message

The actual size of level-1 stream table is l1size. This looks like an
oversight on commit d2e88e7c081ef ("iommu/arm-smmu: Fix LOG2SIZE setting
for 2-level stream tables") which forgot to update the @size in error
message as well.

As memory allocation failure is already bad enough, nothing worse would
happen. But let's be careful.

Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20200826141758.341-1-yuzenghui@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>