wireless_space: set myself as maintainer

LaCie Wireless Space has no defined maintainer.
Set myself as maintainer, since I own one of these.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>

board/LaCie/wireless_space/MAINTAINERS

 WIRELESS_SPACE BOARD
-#M:	-
+M:	Albert ARIBAUD <albert.u.boot@aribaud.net>
 S:	Maintained
 F:	board/LaCie/wireless_space/
 F:	include/configs/wireless_space.h