powerpc: xes: Add maintainer

Add Peter Tyser as the maintainer of Extreme Engineering Solutions products.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
diff --git a/board/xes/xpedite520x/MAINTAINERS b/board/xes/xpedite520x/MAINTAINERS
index 2fd4ac0..f7bd437 100644
--- a/board/xes/xpedite520x/MAINTAINERS
+++ b/board/xes/xpedite520x/MAINTAINERS
@@ -1,5 +1,5 @@
 XPEDITE520X BOARD
-#M:	-
+M:	Peter Tyser <ptyser@xes-inc.com>
 S:	Maintained
 F:	board/xes/xpedite520x/
 F:	include/configs/xpedite520x.h