samples: vfio-mdev: Fix missing pci_disable_device() in mdpy_fb_probe()

Add missing pci_disable_device() in fail path of mdpy_fb_probe().
Besides, fix missing release functions in mdpy_fb_remove().

Fixes: cacade1 ("sample: vfio mdev display - guest driver")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Link: https://lore.kernel.org/r/20221208013341.3999-1-shangxiaojing@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Author: Shang XiaoJing

samples/vfio-mdev/mdpy-fb.c

@@ -109,7 +109,7 @@ static int mdpy_fb_probe(struct pci_dev *pdev,
 
 	ret = pci_request_regions(pdev, "mdpy-fb");
 	if (ret < 0)
-		return ret;
+		goto err_disable_dev;
 
 	pci_read_config_dword(pdev, MDPY_FORMAT_OFFSET, &format);
 	pci_read_config_dword(pdev, MDPY_WIDTH_OFFSET,	&width);
@@ -191,6 +191,9 @@ static int mdpy_fb_probe(struct pci_dev *pdev,
 err_release_regions:
 	pci_release_regions(pdev);
 
+err_disable_dev:
+	pci_disable_device(pdev);
+
 	return ret;
 }
 
@@ -199,7 +202,10 @@ static void mdpy_fb_remove(struct pci_dev *pdev)
 	struct fb_info *info = pci_get_drvdata(pdev);
 
 	unregister_framebuffer(info);
+	iounmap(info->screen_base);
 	framebuffer_release(info);
+	pci_release_regions(pdev);
+	pci_disable_device(pdev);
 }
 
 static struct pci_device_id mdpy_fb_pci_table[] = {