UBI: prepare debugging stuff to further debugfs conversion

We'll need the 'struct ubi_device *ubi' pointer in every debugging function (to
access the ->dbg field), so add this pointer to all the functions implementing
UBI debugging test modes like 'ubi_dbg_is_bitflip()' etc.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
index e23d611..6ba55c2 100644
--- a/drivers/mtd/ubi/io.c
+++ b/drivers/mtd/ubi/io.c
@@ -212,7 +212,7 @@
 	} else {
 		ubi_assert(len == read);
 
-		if (ubi_dbg_is_bitflip()) {
+		if (ubi_dbg_is_bitflip(ubi)) {
 			dbg_gen("bit-flip (emulated)");
 			err = UBI_IO_BITFLIPS;
 		}
@@ -281,7 +281,7 @@
 			return err;
 	}
 
-	if (ubi_dbg_is_write_failure()) {
+	if (ubi_dbg_is_write_failure(ubi)) {
 		dbg_err("cannot write %d bytes to PEB %d:%d "
 			"(emulated)", len, pnum, offset);
 		ubi_dbg_dump_stack();
@@ -396,7 +396,7 @@
 	if (err)
 		return err;
 
-	if (ubi_dbg_is_erase_failure()) {
+	if (ubi_dbg_is_erase_failure(ubi)) {
 		dbg_err("cannot erase PEB %d (emulated)", pnum);
 		return -EIO;
 	}