remove a few unused constant for size of buffers

As pointed by gcc, a few constants which contain sizes for buffers are not
used anywhere in the code. This is probably due to code cleanup, where
these buffers have been removed or where size is automatically calculated
by using 'sizeof' instead to reduce risk of bugs.

Signed-off-by: Christophe CURIS <christophe.curis@free.fr>

src/workspace.c

@@ -57,7 +57,6 @@
 /* index of the first workspace menu entry */
 #define MC_WORKSPACE1   3
 
-#define MAX_SHORTCUT_LENGTH 32
 #define WORKSPACE_NAME_DISPLAY_PADDING 32
 
 static WMPropList *dWorkspaces = NULL;