rpmsg: qcom_smd: Fix irq_of_parse_and_map() return value

The irq_of_parse_and_map() returns 0 on failure, not a negative ERRNO.

Fixes: 53e2822e ("rpmsg: Introduce Qualcomm SMD backend")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220422105326.78713-1-krzysztof.kozlowski@linaro.org

drivers/rpmsg/qcom_smd.c

@@ -1407,7 +1407,7 @@ static int qcom_smd_parse_edge(struct device *dev,
 		edge->name = node->name;
 
 	irq = irq_of_parse_and_map(node, 0);
-	if (irq < 0) {
+	if (!irq) {
 		dev_err(dev, "required smd interrupt missing\n");
 		ret = irq;
 		goto put_node;