fbdev: savage: Handle err return when savagefb_check_var failed

The commit 04e5eac8("fbdev: savage: Error out if pixclock equals zero")
checks the value of pixclock to avoid divide-by-zero error. However
the function savagefb_probe doesn't handle the error return of
savagefb_check_var. When pixclock is 0, it will cause divide-by-zero error.

Fixes: 04e5eac8 ("fbdev: savage: Error out if pixclock equals zero")
Signed-off-by: Cai Xinchen <caixinchen1@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>

drivers/video/fbdev/savage/savagefb_driver.c

@@ -2276,7 +2276,10 @@ static int savagefb_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	if (info->var.xres_virtual > 0x1000)
 		info->var.xres_virtual = 0x1000;
 #endif
-	savagefb_check_var(&info->var, info);
+	err = savagefb_check_var(&info->var, info);
+	if (err)
+		goto failed;
+
 	savagefb_set_fix(info);
 
 	/*