* automake.in (%transformed_files): New variable.

* automake.in (%transformed_files): New variable.
(initialize_per_input): Reset it.
(make_paragraphs): Fill %transformed_files, and define %FIRST%
each time a file is transformed for the first time.
(handle_configure): Do not define %FIRST_CONFIG_HIN%.
(am_install_var): Do not define %FIRST%.
* lib/am/remake-hdr.am: Use %?FIRST% instead of %?FIRST_CONFIG_HIN%.