busybox

- add option 'w' to ps (wide output, optional feature defaults to off).
- move to ENABLE_ and use shorter boilerplate.

sizes without selinux-support:
   text	   data	    bss	    dec	    hex	filename
    356	      0	      0	    356	    164	procps/ps.o.with-w
    300	      0	      0	    300	    12c	procps/ps.o.no-w
    302	      0	      0	    302	    12e	procps/ps.o.oorig