OMAPDSS: HDMI: fix devm_ioremap_resource error checks

devm_ioremap_resource returns ERR_PTR on error, not NULL. Fix the
error checks in the driver.

Signed-off-by: Tomi Valkeinen <[e-mail]>

drivers/video/fbdev/omap2/dss/hdmi4_core.c

···
 	}
 
 	core->base = devm_ioremap_resource(&pdev->dev, res);
-	if (!core->base) {
+	if (IS_ERR(core->base)) {
 		DSSERR("can't ioremap CORE\n");
-		return -ENOMEM;
+		return PTR_ERR(core->base);
 	}
 
 	return 0;

drivers/video/fbdev/omap2/dss/hdmi5_core.c

···
 	}
 
 	core->base = devm_ioremap_resource(&pdev->dev, res);
-	if (!core->base) {
+	if (IS_ERR(core->base)) {
 		DSSERR("can't ioremap HDMI core\n");
-		return -ENOMEM;
+		return PTR_ERR(core->base);
 	}
 
 	return 0;

drivers/video/fbdev/omap2/dss/hdmi_phy.c

···
 	}
 
 	phy->base = devm_ioremap_resource(&pdev->dev, res);
-	if (!phy->base) {
+	if (IS_ERR(phy->base)) {
 		DSSERR("can't ioremap TX PHY\n");
-		return -ENOMEM;
+		return PTR_ERR(phy->base);
 	}
 
 	return 0;

drivers/video/fbdev/omap2/dss/hdmi_pll.c

···
 	}
 
 	pll->base = devm_ioremap_resource(&pdev->dev, res);
-	if (!pll->base) {
+	if (IS_ERR(pll->base)) {
 		DSSERR("can't ioremap PLLCTRL\n");
-		return -ENOMEM;
+		return PTR_ERR(pll->base);
 	}
 
 	return 0;

drivers/video/fbdev/omap2/dss/hdmi_wp.c

···
 	}
 
 	wp->base = devm_ioremap_resource(&pdev->dev, res);
-	if (!wp->base) {
+	if (IS_ERR(wp->base)) {
 		DSSERR("can't ioremap HDMI WP\n");
-		return -ENOMEM;
+		return PTR_ERR(wp->base);
 	}
 
 	return 0;