drm/msm/dsi: fix irq_of_parse_and_map() error checking

The irq_of_parse_and_map() function returns zero on error.  It
never returns negative error codes.  Fix the check.

Fixes: a689554b ("drm/msm: Initial add DSI connector support")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/557715/
Link: https://lore.kernel.org/r/4f3c5c98-04f7-43f7-900f-5d7482c83eef@moroto.mountainSigned-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>

drivers/gpu/drm/msm/dsi/dsi_host.c

@@ -1906,10 +1906,9 @@ int msm_dsi_host_init(struct msm_dsi *msm_dsi)
 	}
 
 	msm_host->irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
-	if (msm_host->irq < 0) {
-		ret = msm_host->irq;
-		dev_err(&pdev->dev, "failed to get irq: %d\n", ret);
-		return ret;
+	if (!msm_host->irq) {
+		dev_err(&pdev->dev, "failed to get irq\n");
+		return -EINVAL;
 	}
 
 	/* do not autoenable, will be enabled later */