[MTD] Fix module refcounting in NAND board drivers.

The _board_ driver needs to be mtd->owner, and it in turn pins the
nand.ko module. Fix them all to actually do that, and fix nand.ko not to
overwrite it -- and also to check that the caller sets it, if the caller
is a module.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

drivers/mtd/nand/au1550nd.c

@@ -345,6 +345,7 @@ int __init au1xxx_nand_init(void)
 
 	/* Link the private data with the MTD structure */
 	au1550_mtd->priv = this;
+	au1550_mtd->owner = THIS_MODULE;
 
 	/* disable interrupts */
 	au_writel(au_readl(MEM_STNDCTL) & ~(1 << 8), MEM_STNDCTL);