UBI: rename IO error code

Rename UBI_IO_BAD_HDR_READ into UBI_IO_BAD_HDR_EBADMSG which is presumably more
self-documenting and readable. Indeed, the '_READ' suffix does not tell much and
even confuses, while '_EBADMSG' tells about uncorrectable ECC error, because we
use -EBADMSG all over the place to represent ECC errors.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c
index 69b52e9..7e7c56d 100644
--- a/drivers/mtd/ubi/scan.c
+++ b/drivers/mtd/ubi/scan.c
@@ -750,7 +750,7 @@
 		bitflips = 1;
 	else if (err == UBI_IO_PEB_EMPTY)
 		return add_to_list(si, pnum, UBI_SCAN_UNKNOWN_EC, &si->erase);
-	else if (err == UBI_IO_BAD_HDR_READ || err == UBI_IO_BAD_HDR) {
+	else if (err == UBI_IO_BAD_HDR_EBADMSG || err == UBI_IO_BAD_HDR) {
 		/*
 		 * We have to also look at the VID header, possibly it is not
 		 * corrupted. Set %bitflips flag in order to make this PEB be
@@ -816,11 +816,11 @@
 		return err;
 	else if (err == UBI_IO_BITFLIPS)
 		bitflips = 1;
-	else if (err == UBI_IO_BAD_HDR_READ || err == UBI_IO_BAD_HDR ||
+	else if (err == UBI_IO_BAD_HDR_EBADMSG || err == UBI_IO_BAD_HDR ||
 		 (err == UBI_IO_PEB_FREE && ec_corr)) {
 		/* VID header is corrupted */
-		if (err == UBI_IO_BAD_HDR_READ ||
-		    ec_corr == UBI_IO_BAD_HDR_READ)
+		if (err == UBI_IO_BAD_HDR_EBADMSG ||
+		    ec_corr == UBI_IO_BAD_HDR_EBADMSG)
 			si->read_err_count += 1;
 		err = add_to_list(si, pnum, ec, &si->corr);
 		if (err)