iommu: qcom-smmu: allow SID 0

It turns out this is a very real stream ID. Who woulda thought?

Drop the 0 check on the SID, there's no reason for it to be there in the first
place.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>

drivers/iommu/qcom-hyp-smmu.c

@@ -134,7 +134,7 @@ static int get_stream_id(struct udevice *dev)
 	int count = ofnode_parse_phandle_with_args(node, "iommus",
 						   "#iommu-cells", 0, 0, &args);
 
-	if (count < 0 || args.args[0] == 0) {
+	if (count < 0) {
 		printf("Error: %s: iommus property not found or wrong number of cells\n",
 		       __func__);
 		return -EINVAL;