setlocale: we need locale.h for LC_ALL on OpenIndiana

--- getopt-1.1.5/nls.h
+++ getopt-1.1.5/nls.h
@@ -40,6 +40,7 @@
 #undef setlocale
 #define setlocale(Category,Locale) /* empty */
 #else /* not WITHOUT_GETTEXT */
+#include <locale.h>
 #include <libintl.h>
 #define _(Text) gettext (Text)
 #endif /* WITHOUT_GETTEXT */