pmic: bd71837: drop DEBUG macro

Drop DEBUG macro definition which is used for debug purpose.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/drivers/power/pmic/bd71837.c b/drivers/power/pmic/bd71837.c
index e292d42..2e04298 100644
--- a/drivers/power/pmic/bd71837.c
+++ b/drivers/power/pmic/bd71837.c
@@ -3,8 +3,6 @@
  * Copyright 2018 NXP
  */
 
-#define DEBUG
-
 #include <common.h>
 #include <errno.h>
 #include <dm.h>