regmap: debugfs: Fix reading in register field units

At the moment, if the length of the register field format is
N bytes, we can only get anything meaningful back to userspace
by providing a buffer that is N + 2 bytes large.  Fix this
so we that we only need to provide a buffer of N bytes.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/base/regmap/regmap-debugfs.c

@@ -185,7 +185,7 @@ static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from,
 		/* If we're in the region the user is trying to read */
 		if (p >= *ppos) {
 			/* ...but not beyond it */
-			if (buf_pos + 1 + map->debugfs_tot_len >= count)
+			if (buf_pos + map->debugfs_tot_len > count)
 				break;
 
 			/* Format the register */