[Toybox] Note to self: singlemake bug.

[Rob Landley]

make top; make ps; ps -A

The -A is a NOP because FLAG(A) is 0 in ps context because ps was switched off
when building top, but ps.o didn't get rebuilt building ps. Dependencies wrong.

Rob

P.S. You wanted more of this stuff going here instead of todo.txt and friends.
No idea when I'll get around to fixing it, "make clean; make ps" works fine for
the moment...