UBI: get rid of dbg_err

This patch removes the 'dbg_err()' macro and we now use 'ubi_err' instead.
The idea of 'dbg_err()' was to compile out some error message to make the
binary a bit smaller - but I think it was a bad idea.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
diff --git a/drivers/mtd/ubi/kapi.c b/drivers/mtd/ubi/kapi.c
index 33ede23..d76fe47 100644
--- a/drivers/mtd/ubi/kapi.c
+++ b/drivers/mtd/ubi/kapi.c
@@ -221,7 +221,7 @@
 	kfree(desc);
 out_put_ubi:
 	ubi_put_device(ubi);
-	dbg_err("cannot open device %d, volume %d, error %d",
+	ubi_err("cannot open device %d, volume %d, error %d",
 		ubi_num, vol_id, err);
 	return ERR_PTR(err);
 }