land: Separate columns x,y and a in output properly

Coordinates run into army when the y coordinate is wider than three
characters.  Has always been broken.  Insert a separating space.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>

src/lib/commands/land.c

@@ -28,6 +28,7 @@
  *
  *  Known contributors to this file:
  *     Steve McClure, 1998
+ *     Markus Armbruster, 2004-2013
  */
 
 #include <config.h>