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>

drivers/mtd/ubi/debug.h

@@ -35,8 +35,6 @@ void ubi_dump_vid_hdr(const struct ubi_vid_hdr *vid_hdr);
 	}                                                                    \
 } while (0)
 
-#define dbg_err(fmt, ...) ubi_err(fmt, ##__VA_ARGS__)
-
 #define ubi_dbg_print_hex_dump(l, ps, pt, r, g, b, len, a)  \
 		print_hex_dump(l, ps, pt, r, g, b, len, a)