sdio: handle cis end marker in link field

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/drivers/mmc/core/sdio_cis.c b/drivers/mmc/core/sdio_cis.c
index 956bd76..6ba93f5 100644
--- a/drivers/mmc/core/sdio_cis.c
+++ b/drivers/mmc/core/sdio_cis.c
@@ -227,6 +227,10 @@
 		if (ret)
 			break;
 
+		/* a size of 0xff also means we're done */
+		if (tpl_link == 0xff)
+			break;
+
 		this = kmalloc(sizeof(*this) + tpl_link, GFP_KERNEL);
 		if (!this)
 			return -ENOMEM;