Update after gnulib changed.

Update after gnulib changed.

* gnulib-local/lib/regex_internal.h.diff: Update.
* gnulib-local/lib/unistd.in.h.diff: Update.
* gettext-runtime/intl/filename.h: New file, from gnulib.
* gettext-runtime/intl/dcigettext.c (ISSLASH, HAS_DEVICE, IS_ABSOLUTE_PATH,
IS_PATH_WITH_DIR): Remove macros. Instead, include filename.h.
(IS_ABSOLUTE_FILE_NAME, IS_RELATIVE_FILE_NAME, IS_FILE_NAME_WITH_DIR): New
macros.
(DCIGETTEXT): Use IS_RELATIVE_FILE_NAME, IS_FILE_NAME_WITH_DIR.
* gettext-runtime/intl/l10nflist.c (ISSLASH, HAS_DEVICE, IS_ABSOLUTE_PATH):
Remove macros. Instead, include filename.h.
(IS_ABSOLUTE_FILE_NAME, IS_RELATIVE_FILE_NAME): New macros.
(_nl_make_l10nflist): Use IS_RELATIVE_FILE_NAME.
* gettext-runtime/intl/Makefile.am (EXTRA_DIST): Add filename.h.
(l10nflist.lo, dcigettext.lo): Depend on it.
* Makefile.am (distcheck-hook): Check also gettext-runtime/intl/filename.h.
* gettext-runtime/intl/lock.c: Update from gnulib.
* gettext-runtime/intl/lock.h: Likewise.
* gettext-runtime/intl/relocatable.c: Likewise.
* gettext-tools/src/locating-rule.c (locating_rule_list_locate): Use
IS_RELATIVE_FILE_NAME instead of IS_ABSOLUTE_PATH.
* gettext-tools/src/open-catalog.c (try_open_catalog_file): Likewise.
* gettext-tools/src/xgettext.c (main, xgettext_open): Likewise.
* libtextstyle/lib/color.c (style_file_lookup): Use IS_FILE_NAME_WITH_DIR
instead of IS_PATH_WITH_DIR.