regulator: hi6421: Fix misleading comment

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/hi6421-regulator.c

@@ -37,7 +37,7 @@ struct hi6421_regulator_pdata {
  * struct hi6421_regulator_info - hi6421 regulator information
  * @desc: regulator description
  * @mode_mask: ECO mode bitmask of LDOs; for BUCKs, this masks sleep
- * @eco_microamp: eco mode load upper limit (in mA), valid for LDOs only
+ * @eco_microamp: eco mode load upper limit (in uA), valid for LDOs only
  */
 struct hi6421_regulator_info {
 	struct regulator_desc	desc;