ACPI/IORT: Rename arm_smmu_v3_set_proximity() 'node' local variable

Commit 36a2ba07757d ("ACPI/IORT: Reject platform device creation on NUMA
node mapping failure") introduced a local variable 'node' in
arm_smmu_v3_set_proximity() that shadows the struct acpi_iort_node
pointer parameter.

Execution was unaffected but it is prone to errors and can lead
to subtle bugs.

Rename the local variable to prevent any issue.

Reported-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Sudeep Holla <sudeep.holla@arm.com>
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index a46c2c1..70c7b79 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -1239,12 +1239,12 @@
 
 	smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
 	if (smmu->flags & ACPI_IORT_SMMU_V3_PXM_VALID) {
-		int node = acpi_map_pxm_to_node(smmu->pxm);
+		int dev_node = acpi_map_pxm_to_node(smmu->pxm);
 
-		if (node != NUMA_NO_NODE && !node_online(node))
+		if (dev_node != NUMA_NO_NODE && !node_online(dev_node))
 			return -EINVAL;
 
-		set_dev_node(dev, node);
+		set_dev_node(dev, dev_node);
 		pr_info("SMMU-v3[%llx] Mapped to Proximity domain %d\n",
 			smmu->base_address,
 			smmu->pxm);