iommu/io-pgtable-arm-v7s: Only kmemleak_ignore L2 tables

iommu/io-pgtable-arm-v7s: Only kmemleak_ignore L2 tables

[ Upstream commit 032ebd8548c9d05e8d2bdc7a7ec2fe29454b0ad0 ]

L1 tables are allocated with __get_dma_pages, and therefore already
ignored by kmemleak.

Without this, the kernel would print this error message on boot,
when the first L1 table is allocated:

[    2.810533] kmemleak: Trying to color unknown object at 0xffffffd652388000 as Black
[    2.818190] CPU: 5 PID: 39 Comm: kworker/5:0 Tainted: G S                4.19.16 #8
[    2.831227] Workqueue: events deferred_probe_work_func
[    2.836353] Call trace:
...
[    2.852532]  paint_ptr+0xa0/0xa8
[    2.855750]  kmemleak_ignore+0x38/0x6c
[    2.859490]  __arm_v7s_alloc_table+0x168/0x1f4
[    2.863922]  arm_v7s_alloc_pgtable+0x114/0x17c
[    2.868354]  alloc_io_pgtable_ops+0x3c/0x78
...

Fixes: e5fc9753b1a8314 ("iommu/io-pgtable: Add ARMv7 short descriptor support")
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>