This reverts commit c5bea524.

This reverts commit b18f6cc1.

- specifies headers that should be ignored. Provides a workaround
  for the fact that wmkdep/wmkdepend doesn't handle defines at all.

STYLE: code cleanup of wmkdep.l

- place wmkdep and dirToString executables under
  utilbin/$(WM_ARCH)$(WM_COMPILER).
  This helps somewhat when copying rules about, and might help when creating
  general rules.