iommu/arm-smmu: fix error return code in arm_smmu_device_dt_probe()

Fix to return -ENODEV instead of 0 when context interrupt number
does no match in arm_smmu_device_dt_probe().

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index ef77e3d..e46a887 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -1852,6 +1852,7 @@
 		dev_err(dev,
 			"found only %d context interrupt(s) but %d required\n",
 			smmu->num_context_irqs, smmu->num_context_banks);
+		err = -ENODEV;
 		goto out_put_parent;
 	}