ARM: Odroid XU3: MAINTAINERS: Add a co-maintainer for OdroidXU3

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/board/samsung/smdk5420/MAINTAINERS b/board/samsung/smdk5420/MAINTAINERS
index 590a114..31c0036 100644
--- a/board/samsung/smdk5420/MAINTAINERS
+++ b/board/samsung/smdk5420/MAINTAINERS
@@ -11,6 +11,7 @@
 
 ODROID-XU3 BOARD
 M:	Jaehoon Chung <jh80.chung@samsung.com>
+M:	Lukasz Majewski <lukma@denx.de>
 S:	Maintained
 F:	board/samsung/smdk5420/
 F:	include/configs/odroid_xu3.h