Improve maintainability by rewriting the mkheader helper.
* src/mkheader.c: New. Based on the mkheader from Libassuan. * src/mkheader.awk: Remove. * src/errnos.in: Add trailing linefeed. * src/gpg-error.h.in: Change meta include directives for use with mkheader.c. * src/Makefile.am (EXTRA_DIST): Replace mkheader.awk by mkheader.c (BUILT_SOURCES): Remove extra-h.in. (CLEANFILES): Remove extra-h.in. Add mkheader.c. (parts_of_gpg_error_h): New. (extra-h.in): Remove rule. (mkheader): Add rule. (gpg-error.h): Change rule to use mkheader.
- Signed-off-by: Werner Koch <wk@gnupg.org>