CVS domivogt: Another width_inc-zero fix attempt.

[cvs]

CVSROOT:        /home/cvs/fvwm
Module name:    fvwm
Changes by:     domivogt        14/09/19 15:24:10

Modified files:
        fvwm           : Tag: branch-2_6 add_window.c 

Log message:
Another width_inc-zero fix attempt.