net: wwan: qcom_bam_dmux: Fix missing pm_runtime_disable()

It's important to undo pm_runtime_use_autosuspend() with
pm_runtime_dont_use_autosuspend() at driver exit time.

But the pm_runtime_disable() and pm_runtime_dont_use_autosuspend()
is missing in the error path for bam_dmux_probe(). So add it.

Found by code review. Compile-tested only.

Fixes: 21a0ffd9 ("net: wwan: Add Qualcomm BAM-DMUX WWAN network driver")
Suggested-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Reviewed-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wwan/qcom_bam_dmux.c

@@ -823,17 +823,17 @@ static int bam_dmux_probe(struct platform_device *pdev)
 	ret = devm_request_threaded_irq(dev, pc_ack_irq, NULL, bam_dmux_pc_ack_irq,
 					IRQF_ONESHOT, NULL, dmux);
 	if (ret)
-		return ret;
+		goto err_disable_pm;
 
 	ret = devm_request_threaded_irq(dev, dmux->pc_irq, NULL, bam_dmux_pc_irq,
 					IRQF_ONESHOT, NULL, dmux);
 	if (ret)
-		return ret;
+		goto err_disable_pm;
 
 	ret = irq_get_irqchip_state(dmux->pc_irq, IRQCHIP_STATE_LINE_LEVEL,
 				    &dmux->pc_state);
 	if (ret)
-		return ret;
+		goto err_disable_pm;
 
 	/* Check if remote finished initialization before us */
 	if (dmux->pc_state) {
@@ -844,6 +844,11 @@ static int bam_dmux_probe(struct platform_device *pdev)
 	}
 
 	return 0;
+
+err_disable_pm:
+	pm_runtime_disable(dev);
+	pm_runtime_dont_use_autosuspend(dev);
+	return ret;
 }
 
 static void bam_dmux_remove(struct platform_device *pdev)