mtd: nand: import nand_hw_control_init()

The code to initialize a struct nand_hw_control is duplicated across
several drivers. Factorize it using an inline function.

Signed-off-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
index d9309cf..b1734d7 100644
--- a/drivers/mtd/nand/s3c2410.c
+++ b/drivers/mtd/nand/s3c2410.c
@@ -977,8 +977,7 @@
 
 	platform_set_drvdata(pdev, info);
 
-	spin_lock_init(&info->controller.lock);
-	init_waitqueue_head(&info->controller.wq);
+	nand_hw_control_init(&info->controller);
 
 	/* get the clock source and enable it */