mtd: nand: Get rid of needless 'goto'

Using "goto" and "switch" statement only makes it harder to follow
control flow and doesn't bring any advantages. Rewrite the code to avoid
using "goto".

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 7f742c9..108adef 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2162,7 +2162,7 @@
 static int nand_read_oob(struct mtd_info *mtd, loff_t from,
 			 struct mtd_oob_ops *ops)
 {
-	int ret = -ENOTSUPP;
+	int ret;
 
 	ops->retlen = 0;
 
@@ -2173,24 +2173,18 @@
 		return -EINVAL;
 	}
 
+	if (ops->mode != MTD_OPS_PLACE_OOB &&
+	    ops->mode != MTD_OPS_AUTO_OOB &&
+	    ops->mode != MTD_OPS_RAW)
+		return -ENOTSUPP;
+
 	nand_get_device(mtd, FL_READING);
 
-	switch (ops->mode) {
-	case MTD_OPS_PLACE_OOB:
-	case MTD_OPS_AUTO_OOB:
-	case MTD_OPS_RAW:
-		break;
-
-	default:
-		goto out;
-	}
-
 	if (!ops->datbuf)
 		ret = nand_do_read_oob(mtd, from, ops);
 	else
 		ret = nand_do_read_ops(mtd, from, ops);
 
-out:
 	nand_release_device(mtd);
 	return ret;
 }