drm/cirrus: Use devm_drm_dev_alloc

Already using devm_drm_dev_init, so very simple replacment.
Acked-by: Noralf Trønnes <noralf@tronnes.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Cc: virtualization@lists.linux-foundation.org
Cc: Emil Velikov <emil.velikov@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200415074034.175360-36-daniel.vetter@ffwll.ch

drivers/gpu/drm/cirrus/cirrus.c

@@ -567,18 +567,13 @@ static int cirrus_pci_probe(struct pci_dev *pdev,
 		return ret;
 
 	ret = -ENOMEM;
-	cirrus = kzalloc(sizeof(*cirrus), GFP_KERNEL);
-	if (cirrus == NULL)
-		return ret;
+	cirrus = devm_drm_dev_alloc(&pdev->dev, &cirrus_driver,
+				    struct cirrus_device, dev);
+	if (IS_ERR(cirrus))
+		return PTR_ERR(cirrus);
 
 	dev = &cirrus->dev;
-	ret = devm_drm_dev_init(&pdev->dev, dev, &cirrus_driver);
-	if (ret) {
-		kfree(cirrus);
-		return ret;
-	}
 	dev->dev_private = cirrus;
-	drmm_add_final_kfree(dev, cirrus);
 
 	cirrus->vram = devm_ioremap(&pdev->dev, pci_resource_start(pdev, 0),
 				    pci_resource_len(pdev, 0));