Merge branch 'jk/make-simplify-dependencies'

Admit that keeping LIB_H up-to-date, only for those that do not use
the automatically generated dependencies, is a losing battle, and
make it conservative by making everything depend on anything.

* jk/make-simplify-dependencies:
  Makefile: drop CHECK_HEADER_DEPENDENCIES code
  Makefile: use `find` to determine static header dependencies
  i18n: treat "make pot" as an explicitly-invoked target

diff --cc Makefile
Simple merge