samsung: espresso7420: change maintainer

Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/board/samsung/espresso7420/MAINTAINERS b/board/samsung/espresso7420/MAINTAINERS
index e3b2394..9145ad4 100644
--- a/board/samsung/espresso7420/MAINTAINERS
+++ b/board/samsung/espresso7420/MAINTAINERS
@@ -1,5 +1,5 @@
 ESPRESSO7420 Board
-M:	Thomas Abraham <thomas.ab@samsung.com>
+M:	Minkyu Kang <mk7.kang@samsung.com>
 S:	Maintained
 F:	board/samsung/espresso7420/
 F:	include/configs/espresso7420.h