Assume setlocale function.

Assume setlocale function.

* gettext-runtime/src/envsubst.c (main): Assume setlocale exists.
* gettext-runtime/src/gettext.c (main): Likewise.
* gettext-runtime/src/ngettext.c (main): Likewise.
* gettext-tools/src/cldr-plurals.c (main): Likewise.
* gettext-tools/src/hostname.c (main): Likewise.
* gettext-tools/src/msgattrib.c (main): Likewise.
* gettext-tools/src/msgcat.c (main): Likewise.
* gettext-tools/src/msgcmp.c (main): Likewise.
* gettext-tools/src/msgcomm.c (main): Likewise.
* gettext-tools/src/msgconv.c (main): Likewise.
* gettext-tools/src/msgen.c (main): Likewise.
* gettext-tools/src/msgexec.c (main): Likewise.
* gettext-tools/src/msgfilter.c (main): Likewise.
* gettext-tools/src/msgfmt.c (main): Likewise.
* gettext-tools/src/msggrep.c (main): Likewise.
* gettext-tools/src/msginit.c (main, canonical_locale_charset, get_title):
Likewise.
* gettext-tools/src/msgmerge.c (main): Likewise.
* gettext-tools/src/msgunfmt.c (main): Likewise.
* gettext-tools/src/msguniq.c (main): Likewise.
* gettext-tools/src/recode-sr-latin.c (main): Likewise.
* gettext-tools/src/urlget.c (main): Likewise.
* gettext-tools/src/xgettext.c (main): Likewise.
* gettext-tools/tests/testlocale.c (main): Likewise.
* gettext-tools/tests/tstgettext.c (main): Likewise.
* gettext-tools/tests/tstngettext.c (main): Likewise.
* gettext-runtime/m4/intl.m4 (AM_INTL_SUBDIR): Don't test whether setlocale
exists.