vmlfb: Fix error handling in cr_pll_init()

There is an error path, where iomemory is left mapped.

Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: NAlexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Alan Hourihane <alanh@fairlite.demon.co.uk>
Signed-off-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>

drivers/video/fbdev/vermilion/cr_pll.c

@@ -185,6 +185,7 @@ static int __init cr_pll_init(void)
 	if (err) {
 		printk(KERN_ERR
 		       "Carillo Ranch failed to initialize vml_sys.\n");
+		iounmap(mch_regs_base);
 		pci_dev_put(mch_dev);
 		return err;
 	}